Comprise vs. Compose


Earlier this year, one intrepid Wikipedia editor made headlines for his remarkable dedication to the mission of purging that website of the phrase “comprised of,” logging approximately 70 to 80 edits per week. This editor, known as Giraffedata, is one of many who hold nonstandard uses of comprise and compose among their top grammatical pet peeves. Today we explore these two terms and the conventions that govern them.

The fundamental difference between comprise and compose has to do with the whole versus the parts of any object or concept. Let’s take a closer look at the definitions to put this in context: comprise is a verb that means “to include or contain” or “to consist of” as in The pie comprises 8 slices. Compose means “to be or constitute a part of element of” or “to make up or form the basis of,” as in Eight slices compose the pie. The key rule to remember is that the whole comprises the elements or parts, and the elements or parts compose the whole.

Their slippery meanings and similar sounds have likely contributed to the rise of “comprised of.” The argument against this phrase is rooted in the definitions outlined above. If we hold comprise strictly to the definition of “to include” or “to consist of,” then “comprised of” sounds awkward: The pie is included of 8 pieces sounds nonsensical, and, by that rule, so too does The pie is comprised of 8 pieces.

To keep writers in the clear, style guides advise avoiding this construction and opting instead for composed of, consisting of, or made up of. However, it is worth noting that “be comprised of” is recorded in dictionaries as synonymous with “be composed of,” and will generally get your point across satisfactorily in informal settings.

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  1. David -  October 19, 2016 - 12:18 pm

    Happy to learn the proper way to use this term. I’ll spread the word among those who I know care about efficient speech.

  2. mark -  April 2, 2016 - 9:08 am

    aside from puns/poetry/politics/marketing/art
    and the like, aren’t words meant mainly to clarify meaning? usage standards should emphasize the important (legal, medical, etc.) differences rather than bicker over petty phrasing, no?
    eg: use of “is comprised of” vs “is composed of” in patent law, use of “shall” vs “will” in contract law, use of “is affected by” vs “is effected by” in physiology, etc. shouldn’t clarity be emphasized ?

    regardless how irritated people become over seeing “irregardless”, isn’t its meaning at least as clear as “they couldn’t agree more” or “they couldn’t agree any more” ? so, why don’t they complain about that, eh?

    • Robert -  June 27, 2016 - 1:31 pm

      Because sloppy language leads to sloppy thinking, and bad usage creeps from blogs and advertising to print to work settings.

      Example: It’s d-mn aggravating when your boss gives you a requirement in mangled English which can be interpreted three ways. Thus, although the boss had no clue and doesn’t want to figure out what the task requires, you get to pick which of the three versions they mean. Should the job encounter a hitch, whatever you picked becomes wrong and that’s your fault. If it goes right, the boss gets credit for dispatching the task correctly.

  3. JedBeetle -  October 18, 2015 - 11:14 am

    This whole discussion is pretty silly, with liberal grammarists defending the evolution of the word comprise to comprise all its incorrect uses, and hardliners defending the nuance to their graves.

    I mean, I don’t care all that much, and a word used incorrectly should be allowed to contain its new definition when used incorrectly enough. This one is pretty funny, though.

    It’s as if people mistook “up” for “down” because they sounded so similar and now use “up” to mean either “up” or “down” and “down” to mean, strictly, “down.”
    It’s kind of a de-evolution and homogenization of language.

  4. Dr. Know -  September 18, 2015 - 9:46 am

    Funnily enough, the opening scene of “The Mothman Prophecies” has one reporter ask another this very question–whether a board is composed of or comprised of a certain number of members. The joke is that the quoted number is wrong, but is followed by the senior reporter responding with, “composed.” Ah, so close, and yet no cigar…

    • Erik Winther Paisley -  October 7, 2016 - 2:16 am

      When in fact, most boards are compromised by their members.

  5. Lenny -  May 18, 2015 - 1:43 pm

    ( ͡°͜ ʖ ͡°)

  6. Eduardo -  May 13, 2015 - 10:28 am

    In patent language we use comprise when making an open statement like “a table comprised of a plurality of legs”. The table has to have more than one leg and can have other stuff also. If you say “composed” like “a table composed of a plurality of legs” the table will have legs… but nothing else.

    A pie comprised of 8 slices

  7. Eduardo -  May 13, 2015 - 10:26 am

    In patent language we use comprise when making an open statement like “a table comprised of a plurality of legs”. The table has to have more than one leg and can have other stuff also. If you say “composed” like “a table composed of a plurality of legs” the table will have legs… but nothing else.

  8. Rosanne Kistler -  May 7, 2015 - 11:16 am

    ‘lie’ does not take an object. It means ‘to assume a lying position’. ‘Lay’ does take an object and means ‘to put or place something’. Examples: I will lie down while reading. I am lying down. I lay on the bed yesterday while I was ill. I have lain on the bed in the past.

    I will lay the book on the table. I am laying the book on the table. I laid the book on the table. I had laid the book on the table before it was taken away.

    The tenses are: lie, lay, have lain; lay, laid, have laid

  9. Riaan -  May 4, 2015 - 12:20 am

    Ending with ““be comprised of” is recorded in dictionaries as synonymous with “be composed of,” “, defies the whole article – so is comprise and compose synonyms or not?

    • Jacko -  May 26, 2015 - 5:36 pm

      They fail to make a conclusion I think.

    • Ron -  July 17, 2015 - 12:05 pm

      No, they is not.

  10. Abbey Road -  May 3, 2015 - 11:21 pm

    Looks as if ‘principal’ v ‘principle’ needs the treatment (again?)!

  11. Samson Lukwanda -  May 3, 2015 - 9:48 pm

    This site is really helpful, thanx 4the hint!

  12. john -  May 3, 2015 - 12:20 pm

    Your definition “Compose means ‘to be or constitute a part of [or] element of’ ” is incorrect and includes a typo. A part cannot compose a whole. The second definition, “to make up or form the basis of,” is better.

  13. richie dee man -  May 2, 2015 - 8:37 am

    good work.i enjoy revising new terms.differentiate for me daily and dairy

  14. Robert Estill -  May 1, 2015 - 10:16 am

    However, it is worth nothing?

  15. David Lee -  May 1, 2015 - 8:40 am

    WIKIPEDIA can’t be trusted. On the 100th anniversary of Wilbur & Orville Wright at KittyHawk Wikipedia incorrectly attributed the Bernoulli effect to the principal of flight. It was not until 2008 that they corrected their error. However, they were not alone on that error; every single major encyclopedia in the world and National Geographic also had the incorrect answer to the principal of flight.

  16. Victor -  April 30, 2015 - 7:37 pm

    While it’s true that ‘The pie is included of 8 pieces.’ sounds awkward, ‘The pie includes 8 pieces.’ does not.

  17. JUAN TISZA -  April 30, 2015 - 5:33 pm


  18. Darby -  April 30, 2015 - 4:07 pm

    Haha. Some of these people online have NO CLUE on what some of these words are. Lucky for me, I’ve read the WHOLE dictionary.com website THREE TIMES!!! I’m a vocab MASTER!!!!!

    • Darby -  April 30, 2015 - 4:08 pm

      Lol I use compose more

    • Katie -  May 1, 2015 - 8:18 pm


      The whole WEBSTER?! 3TIMES?! That’s CRAZY, but ITS TOO FANTASTIC!! And yet I have not met you, but still want to believe it true?! I see it as POSSIBLE?!

      I salute you DICTIONARY-READER-PERSON!! I’d like to share, it was once on my goal-chart to read a Dictionary any dictionary?! Accepting my inability to keep focus, I sorta knew that particular goal would never have a horizontal line running through it! And yet, “I want to” read the dictionary front2black; however, “a once good goal” remains solid, and fixed in my “blind’s eye”with NO WAY OUT!

      Hum, things are strange in this paragraph. -lol-

    • Katie -  May 1, 2015 - 8:30 pm



      That’s CRAZY!

      And yet I have not met you, but still want to believe it true?! I see it as POSSIBLE?!


      I’d like to share, “it” was once one my goals-charted dreams to read a Dictionary any dictionary -from Front2Black!

      Accepting my inability to keep focus keep me focused!

      I sorta knew that particular good-meaning-goal would never have a horizontal line running through it!

      And yet, “I still want to” read the dictionary, yes! Again, Front2Black;

      However, that “a once-good-goal” will have to wait-in-the-15-Or-Less Isle, for IT remains
      solidly-fixed in my “Blind’s Eye” with NO WAY OUT!

      Hum, things are strange in this paragraph.”

      • Ron -  July 17, 2015 - 12:11 pm

        Katie, “Dictionary.com” is not the “Webster dictionary”.

  19. Betsy Mullen -  April 30, 2015 - 3:12 pm

    Most of your word facts are quite clear and understandable. Maybe it’s me but i thought this one was very confusing. I didn’t get it at all.

    • Amy -  June 15, 2015 - 2:36 pm

      This one was harder to understand… I’m not sure I’ve seen this phrase very often, anyway.

  20. Pamela -  April 30, 2015 - 2:04 pm

    I quite agree: it is worth “nothing” that “be comprised of” is recorded in dictionaries as synonymous with “be composed of”…

    P.S. My compliments to Girraffedata.

    • Pamela -  April 30, 2015 - 2:08 pm

      Giraffedata, not “Girraffedata.”

  21. Everett -  April 30, 2015 - 1:42 pm

    I don’t see the issue. If comprise doesn’t work because to say, “the pie is incuded of 8 pieces” is nonsensical, then let’s evaluate the alternative word the same way (ignoring tenses). Compose means to make up or form the basis of. So, applying the same sense to that word, the sentence “The pie is composed of eight pieces” becomes “The pie is to be or constitute a part of eight pieces” makes even less sense. In fact, I could more easily argue that you’re saying the pie makes up part of the eight pieces you meant to say made up the pie. By the logic provided, we should simply snicker at Giraffedata and move along with our productive lives.

    I argue that anyone who looks confused when you say, “this pie comprises 8 slices” either doesn’t know what pie you’re talking about, or doesn’t agree with your slice count.

    • Shaun -  May 4, 2015 - 9:43 am

      Does not compute…error…erroror…errrrrrrrr……..

    • John Sumser -  May 28, 2015 - 10:53 am

      I think your last sentence gets to the heart of the matter. The confusion — which I think would be rare — would be about the pie or the slice count. Personally, I think that anyone who describes the slices in a pie using comprise, compose, or includes does not have a very good grasp of English.

      • Amy -  June 15, 2015 - 2:31 pm

        Can’t we just say, “The pie has 8 slices”?????

    • Kate -  May 28, 2015 - 6:44 pm

      Now I’m hungry. The pie did not comprise my dinner. :-(

    • David -  October 19, 2016 - 12:16 pm

      I applaud your balanced analysis of both “composed of” and “comprised of,” but I must point out that “composed of” actually does make sense. If “composed” means “to make up” or “form the basis of”, and we take the sentence “The pie is composed of eight pieces,” then the befitting definition of composed for the sentence is “to make up,” which becomes “The pie is made up of eight pieces.”

      Now, substituting a word with “the exact wording used in a definition provided for it” is a dangerous practice, and I think Dictionary.com is fortunate it worked out in this case. But ultimately, Giraffedata has practically lost the war for the purity of comprise’s definition; if you look at this site’s definition of the word and Webster’s definition, you’ll see both include a meaning for the word that is identical to “compose.” It was given this secondary definition in the 19th century, (most likely due to its repeated misuse) though “comprise” appeared in the 15th. Now, having these 2 inverse definitions, using comprise has the potential to confuse a reader, and it started with people not being taught properly or bothering to remember the right way something is used (and there is no merit or increased efficiency in that).. So I suppose I see why Giraffedata is trying to keep the clarity in the word. I may just do the same, in my own very small way. :/

  22. Shoshi -  April 30, 2015 - 12:16 pm

    This was a truly helpful word fact for me as I have never used comprise or compse when writing because I have never known their proper usage.

    Thank you.

  23. Amani Abaza -  April 30, 2015 - 11:01 am

    It’s really very beneficial…Thank U…

  24. PKKuhl -  April 30, 2015 - 11:00 am

    If dictionaries have “be comprised of” as synonymous with “be composed of” then it appears they are the ones that need to change. I want to be correct NOT satisfactorily get my point across.

  25. Dottie G. -  April 30, 2015 - 11:00 am

    Thank goodness for that saving grace of ‘informal settings’ :)

  26. Ricky Forguson -  April 30, 2015 - 10:51 am

    Sheesh……..Just when you think you deserve a merit badge in Grammar along comes Dictionary.com, rubbing their schticks together, setting those dreams on fire. I can’t get past “irregardless”– that ‘word’ drives me up a wall. Now I have to kvetch over “comprise vs. compose”?? Oy Vey!!!

  27. Lea -  April 30, 2015 - 10:44 am

    Would you differentiate between “lie” and “lay”?
    Sometimes these two words are interchanged incorrectly.


  28. Jonathan Farber PhD -  April 30, 2015 - 10:33 am

    This is a good one — common and frequently misused, and clearly explained here. Thanks.

    • Ricky -  May 1, 2015 - 8:01 pm

      Dr. Farber (I know you can’t get enough of this honorific), there’s no way you have your doctorate in language arts! Your reply was as generic as a politician’s! Try again…this time with feeling.

  29. Bhanu pratap singh rsthore -  April 30, 2015 - 12:49 am

    Send me word facts weekly


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