un·til 
(ŭn-tĭl)
(ŭn-tĭl)prep.
1. Up to the time of: We danced until dawn.
2. Before (a specified time): She can't leave until Friday.
3. Scots Unto; to.
conj.
1. Up to the time that: We walked until it got dark.
2. Before: You cannot leave until your work is finished.
3. To the point or extent that: I talked until I was hoarse. See Usage Note at till2.
[Middle English : un-, up to (from Old Norse und; see ant- in the Appendix of Indo-European roots) + til, till; see TILL2.]