The words complement and compliment are commonly confused in English. Once you’ve read through this lesson, your friends will compliment you on your mastery of English.
Complement is a noun and verb. It also has a matching adjective, complementary. In any case, it refers to something that completes or goes well with something.
Compliment is also a noun and a verb. It indicates the offering of praise or flattery to another person, as does the adjective complimentary.
Complimentary can also mean free.
The Bottom Line
The word pairs complement/compliment and complementary/complimentary are pronounced identically, hence the confusion in spelling. Just remember that complement with an E means "to complete" or "to enhance," while compliment with an I means "to praise" and complimentary means "free."
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