what is the different between 'till' and 'until'?

[Behnam]

it 'till' used as a slang word?

[Milanya]

No difference. The words are synonyms. "Until" is a bit more formal. (IMO)
_________________
con·text - The part of a text or statement that surrounds a particular word or passage and determines its meaning.

[Sahid59]

..

Dictionary sees no difference. For "till," it gives the following:
preposition:
1. to the time of; up to; until. He slept till noon.
2. before: with the negative. I can't go till noon.
conjunction:
1. up to such time as; until. Till death do us part.
2. before: with the negative. They couldn't go till he came.

For "until," the definitions are the same. The origin is the Old English word "til," meaning "to." "Until takes an Old English prefix, "un," meaning up to, as far as.

..
_________________
Sahid59

Better tomorrow with better English

[Dieter Radke]

the different are two letters u and n ! It's cuttet short!