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; by ( def. ), cause ( def. )

Example Sentences

Because of this structure, perovskites are already widely studied for use in optoelectronics and advanced solar cells.

From Science Daily

Progress has been slow because their fossil record is limited and their genomes are complex.

From Science Daily

Because cells cannot generate enough energy, the brain and muscles are particularly affected.

From Science Daily

Because so few patients are available, large clinical trials are difficult to conduct.

From Science Daily

Because of this, people with high blood pressure should consult a health care professional before making the switch.

From Science Daily