: what one or ones of a group : what particular one or ones
Full Definition of WHICH
: being what one or ones out of a group —used as an interrogative <which tie should I wear><kept a record of which employees took their vacations in July>
:whichever<it will not fit, turn it which way you like>
—used as a function word to introduce a nonrestrictive relative clause and to modify a noun in that clause and to refer together with that noun to a word or word group in a preceding clause or to an entire preceding clause or sentence or longer unit of discourse <in German, which language might … have been the medium of transmission — Thomas Pyles><that this city is a rebellious city… : for which cause was this city destroyed — Ezra 4:15 (Authorized Version)>
—used as a function word to introduce a relative clause ; used in any grammatical relation except that of a possessive ; used especially in reference to animals, inanimate objects, groups, or ideas <the bonds which represent the debt — G. B. Robinson><the Samnite tribes, which settled south and southeast of Rome — Ernst Pulgram> ; used freely in reference to persons as recently as the 17th century <our Father which art in heaven — Matthew 6:9(Authorized Version)>, and still occasionally so used but usually with some implication of emphasis on the function or role of the person rather than on the person as such <chiefly they wanted husbands, which they got easily — Lynn White> ; used by speakers on all educational levels and by many reputable writers, though disapproved by some grammarians, in reference to an idea expressed by a word or group of words that is not necessarily a noun or noun phrase <he resigned that post, after which he engaged in ranching — Current Biography>
That, which, who: In current usage that refers to persons or things, which chiefly to things and rarely to subhuman entities, who chiefly to persons and sometimes to animals. The notion that that should not be used to refer to persons is without foundation; such use is entirely standard. Because that has no genitive form or construction, of which or whose must be substituted for it in contexts that call for the genitive.
That, which: Although some handbooks say otherwise, that and which are both regularly used to introduce restrictive clauses in edited prose. Which is also used to introduce nonrestrictive clauses. That was formerly used to introduce nonrestrictive clauses; such use is virtually nonexistent in present-day edited prose, though it may occasionally be found in poetry.
First Known Use of WHICH
before 12th century
WHICH Defined for Kids
Definition of WHICH for Kids
: what certain one or ones <Which hat should I wear?>
Definition of WHICH for Kids
: which one or ones <Which is the right answer?>
—used in place of the name of something other than people at the beginning of a clause <He needs help, which we can provide.><The idea which you had was good.>