unless

American  

[uhn-les, uhn-] / ʌnˈlɛs, ən- /

conjunction

1. except under the circumstances that.

   I'll be there at nine, unless the train is late.

---

preposition

1. except; but; save.

   Nothing will come of it, unless disaster.

unless British  

/ ʌnˈlɛs /

conjunction

1. (subordinating) except under the circumstances that; except on the condition that

   they'll sell it unless he hears otherwise

---

preposition

1. rare except

Etymology

Origin of unless

1400–50; late ME prepositional phrase on less (also o less(e) , earlier upon less ) on a lesser footing or condition (than); first used as a preposition and conjunction in the early 16th century; see on, less

Example Sentences

“We can never understand inclusion unless we’ve been excluded.”

From Los Angeles Times • May 19, 2026

PlayStation did not specify where the rises would apply, but said they do not apply to current subscribers, except in Turkey or India, unless the existing subscription changes or lapses.

From BBC • May 18, 2026

"But the UAE will still be cautious. It wants to avoid being dragged into open escalation unless it has strong external backing."

From Barron's • May 18, 2026

“There is no historical precedent that the merged entity will share that increased profitability with customers in the form of lower prices or noticeably increased reliability, unless required to,” he said.

From MarketWatch • May 18, 2026

“My daddy won’t be able to remember his favorite shirt unless you start talking!”

From "The Manifestor Prophecy" by Angie Thomas