which
/wɪtʃ
/interrogative pronoun & determiner
Asking for information specifying one or more people or things from a definite set: [as pronoun]: which are the best varieties of grapes for long keeping? which of the suspects murdered him? [as determiner]: which way is the wind blowing?...
- What do you feel about this friend and which of his or her qualities do you see in yourself?
relative pronoun & determiner
Used referring to something previously mentioned when introducing a clause giving further information: [as pronoun]: a conference in Vienna which ended on Friday [after preposition]: it was a crisis for which he was totally unprepared [as determiner, after preposition]: your claim ought to succeed, in which case the damages will be substantial...
- The game can also end if the stock runs out of cards, in which case the result is a draw.
- So we do not need to step out of the house for days, which I am so looking forward to.
- Cars go out in the first session in the order in which they finished the previous race.
Usage
On the differences between which and that in relative clauses, see that (usage).
Phrases
which is which
Origin
Old English hwilc, from the Germanic bases of who and alike.