When paying someone a compliment like “I love what you’ve done with the kitchen!” you’re being complimentary. A free bonus item is also a complimentary gift. But items or people that go well with each other are complementary.
In geometry, complementary angles add up to 90°, whereas supplementary ones add up to 180°.
This week on the podcast, hot is the word. Also Paul Brians’ latest blog post discusses an interesting misspelling.