in or at what place?: Where is he? Where do you live?
2.
in what position or circumstances?: Where do you stand on this question? Without money, where are you?
3.
in what particular respect, way, etc.?: Where does this affect us?
4.
to what place, point, or end? whither?: Where are you going?
5.
from what source? whence?: Where did you get such a notion?
–conjunction
6.
in or at what place, part, point, etc.: Find where he is. Find where the trouble is.
7.
in or at the place, part, point, etc., in or at which: The book is where you left it.
8.
in a position, case, etc., in which: Where ignorance is bliss, 'tis folly to be wise.
9.
in any place, position, case, etc., in which; wherever: Use the ointment where pain is felt.
10.
to what or whatever place; to the place or any place to which: I will go where you go.
11.
in or at which place; and there: They came to the town, where they lodged for the night.
–pronoun
12.
what place?: Where did you come from?
13.
the place in which; point at which: This is where the boat docks. That was where the phone rang.
–noun
14.
a place; that place in which something is located or occurs: the wheres and hows of job hunting.
—Idiom
15.
where it's at, Slang. where the most exciting, prestigious, or profitable activity or circumstance is to be found.
Origin: bef. 900; ME quher, wher, OE hwǣr; c. D waar, OHG hwār; akin to ON hvar, Goth hwar
Usage note: Where … at (Where was he at?) and where … to (Where is this leading to?) are often criticized as redundant because neither at nor to adds anything to the meaning of where, and sentences like the preceding ones are perfectly clear and standard without the final at or to. This criticism does not apply to where … from, which is fully standard: Where does the money come from? The constructions where … at and where … to occur in the speech of educated people but are rare in formal speech and edited writing.
In what situation or position: Where would we be without your help?
From what place or source: Where did you get this idea?
To what place; toward what end: Where is this argument leading?
conj.
At what or which place: She moved to the city, where jobs are available.
In a place in which: He lives where the climate is mild.
In any place or situation in which; wherever: Where there's smoke, there's fire.
To a place in which: We should go where it is quieter.
To a place or situation in which: They will go where they are happy.
To a place in which: We should go where it is quieter.
To a place or situation in which: They will go where they are happy.
n.
The place or occasion: We know the when but not the where of it.
What place, source, or cause: Where are you from?
[Middle English, from Old English hwǣr; see kwo- in Indo-European roots.]
Usage Note: When where is used to refer to a point of origin, the preposition from is required: Where did she come from? From where I sit, the situation looks bleak. When it is used to refer to a destination, the preposition to is generally superfluous: Where is she going (rather than Where is she going to)? The place where they are going is beautiful.. When it is used to refer to the location of a person, event, or structure, the use of at is widely regarded as regional or colloquial: Where is the station (not Where is the station at)? Where he is, he has no access to a good library. See Usage Note at why.
[hwair, wair] 
