Compound Nouns

A compound noun is a noun that is made with two or more words. A compound noun is usually [noun + noun] or [adjective + noun], but there are other combinations (see below). It is important to understand and recognize compound nouns. Each compound noun acts as a single unit and can be modified by adjectives and other nouns.

There are three forms for compound nouns:

1. open or spaced - space between words (tennis shoe)
2. hyphenated - hyphen between words (six-pack)
3. closed or solid - no space or hyphen between words (bedroom)

Here are some examples of compound nouns:

Pronunciation

Compound nouns tend to have more stress on the first word. In the phrase "pink ball", both words are equally stressed (as you know, adjectives and nouns are always stressed). In the compound noun "golf ball", the first word is stressed more (even though both words are nouns, and nouns are always stressed). Since "golf ball" is a compound noun we consider it as a single noun and so it has a single main stress - on the first word. Stress is important in compound nouns. For example, it helps us know if somebody said "a GREEN HOUSE" (a house which is painted green) or "a GREENhouse" (a building made of glass for growing plants inside).

British/American differences

Different varieties of English, and even different writers, may use the open, hyphenated or closed form for the same compound noun. It is partly a matter of style. There are no definite rules. For example we can find:

• container ship
• container-ship
• containership

If you are not sure which form to use, please check in a good dictionary.

Plural Forms of Compound Nouns

In general we make the plural of a compound noun by adding -s to the "base word" (the most "significant" word). Look at these examples:

Note that there is some variation with words like spoonful or truckful. The old style was to say spoonsful or trucksful for the plural. Today it is more usual to say spoonfuls or truckfuls. Both the old style (spoonsful) and the new style (spoonfuls) are normally acceptable, but you should be consistent in your choice. Here are some examples:

Some compound nouns have no obvious base word and you may need to consult a dictionary to find the plural:

• higher-ups
• also-rans
• go-betweens
• has-beens
• good-for-nothings
• grown-ups

Note that with compound nouns made of [noun + noun] the first noun is like an adjective and therefore does not usually take an -s. A tree that has apples has many apples, but we say an apple tree, not apples tree; matchbox not matchesbox; toothbrush not teethbrush.

With compound nouns made of [noun + noun] the second noun takes an -s for plural. The first noun acts like an adjective and as you know, adjectives in English are invariable. Look at these examples: