Contranym

A contranym is a word that can be its own opposite.

Contranyms — like a heteronym, portemanteau, palindrome and semordnilap — are neat things to look out for. Like how you can dust something to pick up dust from a surface and dust that surface to remove dust from it.

So versatile. Or perhaps confusing.

I learned this from Kathryn Schulz’ excellent article, What part of “No, totally” don’t you understand , about how “no, totally” came to mean “yes.”