from The American Heritage® Dictionary of the English Language, 4th Edition
- adv. To what place; toward what end.
- conj. To which.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adv. To what; to which place, whither?
- adv. To what end; why?
- adv. To which.
from the GNU version of the Collaborative International Dictionary of English
- adv. To which; -- used relatively.
- adv. To what; to what end; -- used interrogatively.
from The Century Dictionary and Cyclopedia
- To what place, point, end, etc.?
- To which; to whom; whither.
From where + to. (Wiktionary)