Origin and Etymology of unless
First Known Use: 14th centurySee Words from the same year
First Known Use of unless
UNLESS Defined for English Language Learners
Definition of unless for English Language Learners
—used to say what will happen, be done, or be true if something else does not happen, is not done, or is not true
UNLESS Defined for Kids
Definition of unless for Students
- You can't have dessert unless you finish your dinner.
Seen and Heard
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