Merriam-Webster's Collegiate® Dictionary, 11th Edition
WHERE
I. adverb see: who Date: before 12th century
1. at, in, or to what place , at, in, or to what situation, position, direction, circumstances, or respect , here , there ,
II. conjunction
Date: 12th century
1. at, in, or to what place , at, in, or to what situation, position, direction, circumstances, or respect , the place or point at, in, or to which , wherever ,
3. at, in, or to which place , at or in which ,
4. at, in, or to the place at, in, or to which , in a case, situation, or respect in which , that ,
III. noun
Date: 15th century
place , location , what place, source, or cause