Compound words are words or expressions formed by combining two or more words.
There are three types of compound words:
-
open: words separated by a space
-
closed: words combined without space
-
hyphenated: words joined together with a hyphen
The spelling of compound words may vary depending on its use.
Open compound words are words or expressions formed from two words separated by a space.
Open compound words are mostly nouns and verbs.
When open compound words form verbs, they are called phrasal verbs.
For example: look out.
|
living |
room |
living room |
|
ice |
cream |
ice cream |
|
cell |
phone |
cell phone |
|
vice |
president |
vice president |
Closed compound words are words or expressions formed by combining two words that could stand on their own.
Closed compound words can belong to most parts of speech.
|
after |
noon |
afternoon |
|
in |
side |
inside |
|
baby |
sit |
babysit |
|
world |
wide |
worldwide |
Hyphenated compound words are words or expressions formed from two or more words separated by a hyphen.
Hyphenated compound words can belong to most parts of speech.
|
well |
+ |
being |
= |
well-being |
|
king |
+ |
size |
= |
king-size |
|
double |
+ |
check |
= |
double-check |
|
self |
+ |
esteem |
= |
self-esteem |
It is also possible to form hyphenated compound words from 3 separate words.
|
sister |
+ |
in |
+ |
law |
= |
sister-in-law |
|
merry |
+ |
go |
+ |
round |
= |
merry-go-round |
|
over |
+ |
the |
+ |
counter |
= |
over-the-counter |
|
word |
+ |
of |
+ |
mouth |
= |
word-of-mouth |
To pluralize open compound words forming nouns, only pluralize the last part of the word (the final word).
|
singular form |
plural form |
|
full moon |
full moons |
|
energy bar |
energy bars |
Closed compound words are only pluralized when they form nouns. To pluralize them, add the -s at the end of the word.
|
singular form |
plural form |
|
wildflower |
wildflowers |
|
dishwasher |
dishwashers |
Each hyphenated compound word forming a noun is pluralized differently.
In most cases, the plural -s is added to the final word.
|
singular form |
plural form |
|
merry-go-round |
merry-go-rounds |
|
grown-up |
grown-ups |
However, when a hyphenated compound word contains more than one noun, the plural -s is added to the noun that exists multiple times.
|
singular form |
plural form |
|
sister-in-law |
sisters-in-law |
|
There are many sisters, not many laws. |
|
|
tractor-trailer |
tractor-trailers |
|
There are many trailers, not many tractors. |
|