Comprise vs. Compose: What’s the Difference?

Compose and comprise sound similar, and they have similar meanings. At the same time, the word “compose” has many definitions that aren’t synonymous with “comprise”. You’ll never hear someone say “a musician comprised an opera” or “she comprised herself before stepping into the room.” Yet, it makes perfect sense to compose an opera or compose oneself. In this article, we’ll focus on a narrow scope. There’s an area of overlap between “comprise” and “compose” that causes many people to stumble over the correct word. We’re going to explain how to avoid confusion. 

The following sentences clarify the basic use cases:

  1. The whole comprises the parts. 
  2. The whole is composed of the parts.
  3. The parts compose the whole.

Both compose and comprise deal with the relationship between the parts and the whole. Let’s imagine a recipe. You may use either word to describe how the parts of the recipe relate to the whole; however, the English language requires that you use them differently. When the subject of the sentence is the whole, you can use the word “comprise” or the passive phrase “is composed of”. In this context, comprise means “contains” and “is composed of” means “is made of.”

The recipe comprises three eggs, a cup of sugar, and three cups of flour.

The recipe is composed of three eggs, a cup of sugar, and three cups of flour.

When the constituent parts are the subject of the sentence, you should stick to “compose”. In this context, compose means “make up.” 

Three eggs, a cup of sugar, and three cups of flour compose the recipe. 

Let’s try it again with 50 states (the parts) and the United States (the whole). 

Here are examples of correct usage:

  1. The United States comprises fifty states. 
  2. The United States is composed of fifty states.
  3. Fifty states compose the United States. 

Although you may have heard people say “is comprised of,” this phrase can lead to mix-ups. We recommend always writing “comprise” in an active voice. The passive voice phrase is undergoing a contextual shift, and many people use “is comprised of” as a substitute for “is composed of.” Most grammarians take issue with this common mistake. The formal meaning of “is comprised of” should be the opposite: “is contained in” or “compose”.  Because the passive phrase can cause misunderstandings, careful writers avoid it. 

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Etymology

Since comprise and compose sound similar, you may wonder whether they come from the same root word. In reality, they developed separately from different Latin origins.

The known history of the word “comprise” begins with the Proto-Indo-European root word ghend-, which means “to seize, take.” The Online Etymology Dictionary explains that the Latin language added the prefixes com- and pre- to form the word comprehendere, meaning “to take together, to unite; include; seize; to comprehend, perceive.” The Latin comprehendere made its way directly into English with the word “comprehend” in the mid 14th century. Meanwhile, in Old French, the past participle compris (from the verb comprendre) came to mean “to contain, comprise.” The French compris became “comprise” in English in the early 15th century, meaning “to include.”

In contrast, “compose” developed from the Late Latin pausare, meaning “to cease, lay down.” This originated with the Greek pauein, which has no known cognates. Pausare passed into the Old French, after combining with the prefix com-, around the 12th century. The Online Etymology Dictionary explains that the Old French word composer, which meant “put together, compound; adjust, arrange; write,” was also influenced by componere “to arrange, direct.” In 1400, the word compousen made its way into English and referred to writing a book. Later in that century, the word adopted the definition “to make or form by uniting two or more things.” The word “compose” came to mean “be the substance or elements of, make up,” the closest definition to “comprise”, in the 1540’s. Later, the word “compose” was applied to music (1500’s), printing (1600’s), and painting (1700’s).

Definitions

Compose is a verb. According to Merriam-Webster, it can mean:

  • to form by putting together
  • to form the substance of
  • to produce (columns, pages of type, etc.) by composition
  • to create by mental or artistic labor
  • to formulate and write (a piece of music)
  • to compose music for
  • to deal with or act on so as to reduce to a minimum
  • to arrange in proper or orderly form
  • to free from agitation

The word “comprise” has fewer applications than “compose”. It means “to be made up of,” “compose, constitute,” or “to include especially within a particular scope.” Although compose and comprise can be synonyms, not all the uses of “compose” are interchangeable with “comprise”. 

Synonyms

According to Thesaurus.com, some synonyms for compose include:

  • belong to
  • build
  • comprise
  • consist of
  • constitute
  • construct
  • form

Thesaurus.com lists the following words as synonyms for comprise:

  • amount to
  • compose
  • constitute
  • contain
  • cover
  • encompass
  • form

Practice Test

See if you can choose the correct word. 

  1. New York comprises/composes several regions between the Atlantic Ocean and Lake Ontario. 
  2. Paragraphs by diverse authors compose/comprise a single Wikipedia page. 
  3. The sentence is composed of/ is comprised of different parts of speech, including adverbs, adjectives, nouns, prepositions, and verbs. 
  4. I am composed of/ comprised of 60% water. 
  5. The digital team comprises/composes specialists with expertise in social media, WordPress, and online marketing. 

Answers: 1) comprises 2) compose 3) is composed of 4) composed of 5) comprises

Sources: 

  1. https://www.thesaurus.com/browse/comprise?s=t
  2. https://www.thesaurus.com/browse/compose?s=t
  3. https://www.etymonline.com/search?q=compose
  4. https://www.etymonline.com/word/comprise
  5. https://www.quickanddirtytips.com/education/grammar/comprise-versus-compose