Definitions
If you say that x is true unless y, x is true only if y does not happen or is not true.
Word origin
From Middle English unlesse, earlier on lesse (modern on + less), from (not) on lesse (than) (“(not) on a less compelling condition (than)”). The quality of negation in the word and the lack of stress changed on to un-.
Used in a sentence
“I’m leaving unless I get a pay rise.”
“You can't go out unless it stops raining.”
“Unless part of the staff, you are not allowed beyond this point.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Except if”6 letters
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