because

[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.
Idioms
2.
because of, by reason of; due to:
Schools were closed because of heavy snowfall.
Origin
1275-1325; Middle English bi cause by cause
Synonyms
1. Because, as, since, for, inasmuch as agree in implying a reason for an occurrence or action. Because introduces a direct reason: I was sleeping because I was tired. As and since are so casual as to imply merely circumstances attendant on the main statement: As (or since ) I was tired, I was sleeping. The reason, proof, or justification introduced by for is like an afterthought or a parenthetical statement: I was sleeping, for I was tired. Inasmuch as implies concession; the main statement is true in view of the circumstances introduced by this conjunction: Inasmuch as I was tired, it seemed best to sleep.
Usage note
1. See reason.
Examples from the web for because
  • Some traditional childhood games are disappearing from school playgrounds because educators say they're dangerous.
  • She is visiting the doctor because of several symptoms.
  • Blogging is no longer what it was, because it has entered the mainstream.
  • Biff won that fight simply because there was no fight.
  • Part of why diets fail is because diet food is often not very satisfying.
  • because this is exactly the kind of move that is getting people so upset with you.
  • If it has not, that may be partly because it insisted that the recession was imported from the outside world.
  • Global warming has kindled the debate further because it has created both hotter and drier conditions in many places.
  • That's because information is not the scarce resource.
  • because they have grown rich, they'll have the means to keep it.
British Dictionary definitions for because

because

/bɪˈkɒz; -ˈkəz/
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) because of, on account of: I lost my job because of her
Word Origin
C14 bi cause, from biby + cause
Word Origin and History for because
conj.

c.1300, bi cause "by cause," modeled on French par cause. Originally a phrase, often followed by a subordinate clause introduced by that or why. One word from c.1400. As an adverb from late 14c. Clipped form cause attested in writing by mid-15c.