Compound nouns, like all compound words, can be formed in three ways:
Closed Form: These compound nouns simply push two words together to form one word, with no additional punctuation or spaces. Examples include softball, redhead, makeup and keyboard.
Hyphenated Form: These compound nouns connect two or more words with a hyphen. Examples include six-pack, five-year-old, and son-in-law2.
Open Form: These are compound nouns that function as one unique word, but are still written as two separate words, with a space between each component. Examples include post office, middle class, and attorney general.
Most compound nouns contain at least one noun. The other word or words used for the compound noun may be an adjective, preposition or verb. The second word is often the "main" word, with the first word modifying it or adding to its meaning.
Compound Noun List
To get a sense of how compound nouns are formed, study the words below. We've listed the examples in groups that indicate the parts of speech that make up each compound noun.
adjective/adjective: red-orange, turquoise blue
Red-orange is one of this year's most popular colors.
adjective/noun: blackboard, full moon
The teacher needed help erasing the blackboard.
adjective/verb: dry-cleaning
Be sure to pick up the dry-cleaning on your way home.
noun/noun: toothpaste, football, fish tank
Toothpaste now comes in many flavors.
noun/preposition: love-in, hanger on, passer-by
During the 1960s, a love-in was a form of peaceful protest.