As interrog. adv. in direct questions: (a) with broadly locative sense: in what?; ~ is bicomen, ?what has become of (sth.)?; (b) with nonlocative sense: in what manner?, in what respect?, how?

As rel. adv. introducing locative adj. clauses: (a) with ref. to a physical place, a geographical feature, a structure, an object, a garment, etc.: in or within which, inside which, in the interior of which, where; also [quot. c1470], ?within the borders of which; ?in the fabric of which; with verbs of motion or placement: into which; also, to which [quot. a1393]; ~ that; (b) with ref. to a book, a prayer, Scripture: in the text of which, in the words of which; (c) with ref. to a monastic foundation or its membership: of or in which.

As rel. adv. introducing adj. clauses, chiefly nonlocative or with very loose locative sense: (a) with ref. to abstractions: in the experience of which, in the doing of which, in which; also, by which, through which; also, with verbs of motion or placement in nonliteral uses: into which, on which; also, that [quot. ?a1425, 3rd]; (b) with loose ref. to preceding predication: in respect of which.

As rel. adv. introducing an inf. phrase of loosely temporal function: during which, in which; the ~.

As subordinating conj. introducing noun clauses usu. functioning as direct obj.: (a) with ref. to a physical location: in what place or thing, where;—functioning as appositive to direct obj.; also with ref. to a nonliteral place [2nd quot.]; (b) with ref. to a nonliteral place or an abstraction: anything in which; (c) with ref. to an abstraction: in what manner, in what respect, how.

As subordinating conj. introducing noun inf. phrases functioning as direct obj., with ref. to an object: a thing in which, anything in which.