Six words that are (sort of) their own opposites

The other morning I was perusing a new crossword puzzle. I had finished Wordle and Connections, but I still had not finished my coffee and wanted to kill another ten minutes… (dear readers, you know what I’m talking about, right?). Anyway, one of the clues was for a word that seemed to have two opposite meanings. The clue read ‘Having departed, and remained behind’. The answer was ‘left’. This sent me down a rabbit hold and I discovered that this is an example of a contranym (also spelled contronym). Contranyms are words that have two meanings that are either opposite or at least contradictory. These are also called Janus words, from the two-faced Roman god Janus.

Here are six of them, defined. Can you guess the words? (answers at the bottom, and in true materials writer style, an example has been done for you at the top). Test a friend, or do this over your morning coffee after your other word games.

having departed; remaining behind

to remove fine particles from something // to apply fine particles to something

watchful care // a mistake made because you didn’t notice something

moving at high speed // immobile because it is stuck in place

to show or broadcast something // to hide or conceal something

to give official approval to something // an official penalty or boycott

Answers: 1 left; 2 dust; 3 oversight; 4 fast; 5 screen; 6 sanction