because

American  

[bih-kawz, -koz, -kuhz] / bɪˈkɔz, -ˈkɒz, -ˈkʌz /

conjunction

1. for the reason that; due to the fact that.

   The boy was absent because he was ill.

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preposition

1. Informal. (used directly before a noun, adjective, verb, interjection, etc., to convey a very concise rationale, excuse, or explanation).

   We’re a little like monkeys because evolution.

   He doesn’t practice enough: because lazy.

   I love doughnuts because yum!

idioms

1. because of, by reason of; due to.

   Schools were closed because of heavy snowfall.

because British  

/ -ˈkəz, bɪˈkɒz /

conjunction

1. (subordinating) on account of the fact that; on account of being; since

   because it's so cold we'll go home

2. (preposition) on account of

   I lost my job because of her

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Usage

See reason.

Etymology

Origin of because

First recorded in 1275–1325; Middle English bi cause; see by ( def. ), cause ( def. )

Example Sentences

Because bile acids enter the bloodstream, they can affect tissues and organs far beyond the digestive system.

From Science Daily • Jun. 9, 2026

“Guess what? They’re doing it now. Why? Because they can’t even get the diesel to give to those islands.”

From Barron's • Jun. 9, 2026

Because Pratt’s campaign was great on the A.I.-generated streets but not the actual city of Los Angeles, the state has become the latest flashpoint for an election panic.

From Slate • Jun. 9, 2026

"Because here she was, the great safeguarder of women. But who was safeguarding her, at her time of need?"

From BBC • Jun. 9, 2026

“Because you had friends. Because you seemed happy.”

From "Bye Forever, I Guess" by Jodi Meadows