A compound noun consists of two or more words that act as a singular noun.

 

All compound nouns contain at least one main word, which is  the last in such combination and in most cases is a noun:

table tennis, playground, school bag, haircut, dishwasher, toothpaste, swimming pool   

 

The other word(s) in this combination may be an adjective, or preposition, or verb. They modify the main word or add to its meaning:

 

We need to go to the bus stop (noun + noun).

 

Take a look at the whiteboard (adjective + noun)

 

The historic city centre is reachable by underground (preposition + noun)

 

Compound nouns can be formed in three different ways:

 

– two words melded together to make one word

 

Jennifer needs some time to fix her makeup.

 

Michael likes playing football.

 

I need a new toothbrush for my trip.

 

– separate words next to each other

 

To receive your parcel you should contact your local post office.

 

Kids have been playing in the  swimming pool  all day long.

 

Please put the plates on the kitchen table, I will wash them later.

 

– hyphenated forms

 

This coat is not suitable for dry-cleaning.

 

All visitors are invited to the hotel reception for check-in.

 

There are two six-packs of beer in my fridge.

 

Plural forms of compound nouns are created by making the final noun plural:

 

Babysitter → Good babysitters always have reference letters from their clients.

 

Haircut → Some haircuts can make your face look thinner.

 

Cycle race → Nick took part in many cycle races.