Usage Tip: Complementary/complimentary

a 59-degree angle adjacent to a 31-degree angle

Another pair of commonly confused words is complementary and complimentary.

Complementary, with an E, means “serving to fill out or complete,” such as when one piece of clothing complements another. Similarly, as you may remember from elementary school art class, colours that are opposite each other on the colour wheel, such as red and green, are called complementary. Meanwhile, in math class, two angles that add up to 90 degrees are also called complementary. In each case, things work together to balance each other out or complete each other.

the colour wheel

Complimentary, with an I, has two meanings. One refers to saying something nice about someone or something – giving them a compliment. The other refers to a free product or service, such as a complimentary breakfast.


If you’re interested in copy editing or proofreading services, email catherinelaiediting@gmail.com or use the contact form at catherinelaiediting.com.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s