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Synonyms

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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

See reason.

Etymology

Origin of because

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