What's the difference between what and which?

What


Definition:

  • (pron., a., & adv.) As an interrogative pronoun, used in asking questions regarding either persons or things; as, what is this? what did you say? what poem is this? what child is lost?
  • (pron., a., & adv.) As an exclamatory word: -- (a) Used absolutely or independently; -- often with a question following.
  • (pron., a., & adv.) Used adjectively, meaning how remarkable, or how great; as, what folly! what eloquence! what courage!
  • (pron., a., & adv.) Sometimes prefixed to adjectives in an adverbial sense, as nearly equivalent to how; as, what happy boys!
  • (pron., a., & adv.) As a relative pronoun
  • (pron., a., & adv.) Used substantively with the antecedent suppressed, equivalent to that which, or those [persons] who, or those [things] which; -- called a compound relative.
  • (pron., a., & adv.) Used adjectively, equivalent to the . . . which; the sort or kind of . . . which; rarely, the . . . on, or at, which.
  • (pron., a., & adv.) Used adverbially in a sense corresponding to the adjectival use; as, he picked what good fruit he saw.
  • (pron., a., & adv.) Whatever; whatsoever; what thing soever; -- used indefinitely.
  • (pron., a., & adv.) Used adverbially, in part; partly; somewhat; -- with a following preposition, especially, with, and commonly with repetition.
  • (n.) Something; thing; stuff.
  • (interrog. adv.) Why? For what purpose? On what account?

Example Sentences:

Which


Definition:

  • (a.) Of what sort or kind; what; what a; who.
  • (a.) A interrogative pronoun, used both substantively and adjectively, and in direct and indirect questions, to ask for, or refer to, an individual person or thing among several of a class; as, which man is it? which woman was it? which is the house? he asked which route he should take; which is best, to live or to die? See the Note under What, pron., 1.
  • (pron.) A relative pronoun, used esp. in referring to an antecedent noun or clause, but sometimes with reference to what is specified or implied in a sentence, or to a following noun or clause (generally involving a reference, however, to something which has preceded). It is used in all numbers and genders, and was formerly used of persons.
  • (pron.) A compound relative or indefinite pronoun, standing for any one which, whichever, that which, those which, the . . . which, and the like; as, take which you will.

Example Sentences: