As a verb incase
As a conjunction unless is
except on a specified condition; if not.
* in case
* unlesse (obsolete)
Except on a specified condition; if not.
* 1839 , Denison Olmsted, A Compendium of Astronomy Page 95
- I’m leaving unless I get a pay rise (AmE: raise).
- Secondly, When a body is once in motion it will continue to move forever, unless something stops it. When a ball is struck on the surface of the earth, the friction of the earth and the resistance of the air soon stop its motion.
* (except on a condition) if
* precisely unless
* unless and until, until and unless