closed compound noun

grammar

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Last updated

July 22, 2026

Quick Summary

A closed compound noun is formed by combining two or more words into a single, unhyphenated word. These words function as a single unit of meaning.1

Examples of closed compound nouns include:
* database
* football
* hairbrush

While some compound words start as open (two words) or hyphenated, they can evolve into closed compounds over time as they become more established in the English language. The styling of compound words can be fluid, but closed compounds are common for established terms.23

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noun
Types of nouns
Some, called closed compound nouns, remain a single word. These include words such as toothbrush, notebook, and sunflower. Hyphenated compound nouns have hyphens in them, as the name suggests. Some examples of hyphenated compound nouns are mother-in-law, passer-by, and merry-go-
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Some, called closed compound nouns, remain a single word. These include words such as toothbrush, notebook, and sunflower. Hyphenated compound nouns have hyphens in them, as the name suggests. Some examples of hyphenated compound nouns are mother-in-law, passer-by, and merry-go-
Read More