1. up to the time of; till (a specified time or occurrence) until payday
2. before (a specified time or occurrence): used with a negative not until tomorrow
3. Scot. to or toward

Etymology: ME untill < un- (see unto) + till, to, till

conjunction

1. up to the time when or that until you leave
2. to the point, degree, or place that heat the water until it boils
3. before: used with a negative not until he tells you