early 15c., "to leave without shelter or defense," from Old French esposer, exposer "lay open, set forth, speak one's mind, explain" (13c.), from Latin exponere "set forth, lay open, exhibit, reveal, publish," from ex "from, forth" (see ex-) + ponere "to put, place" (see position (n.)). Altered in French by confusion with poser "to place, lay down" (see pose (v.1)). Meaning "to exhibit openly" is from 1620s; that of "to unmask" is from 1690s. Photographic sense is from 1839. Related: Exposed; exposes; exposing.
c. 1400, compousen, "to write" (a book), from Old French composer "put together, compound; adjust, arrange; write" a work (12c.), from com- "with, together" (see com-) + poser "to place," from Late Latin pausare "to cease, lay down" (see pause (n.)).
Meaning influenced in Old French by componere "to arrange, direct" (see composite; also see compound (v.), pose (v.)), which gradually was replaced in French by composer. Similar confusion is found in expose, oppose, repose (v.2), transpose, etc.
Meaning "to make or form by uniting two or more things" is from late 15c. Sense of "be the substance or elements of, make up" is from 1540s. Sense of "invent and put (music) into proper form" is from 1590s. From c. 1600 as "bring into a composed state, to cal, quiet;" from 1650s as "place (parts or elements) in proper form, arrange."
In painting, "combine into an arrangement with artistic effect" (1782). In printing, "put into type" (1630s), but the usual term among printers was set. Related: Composed; composing. The printers' composing room is from 1737.
early 15c., "uncover, lay bare, expose, disclose, reveal," a sense now obsolete, from Latin detectus, past participle of detegere "uncover, expose," figuratively "discover, reveal, disclose," from de "un-, off" (see de-) + tegere "to cover," from PIE root *(s)teg- "to cover."
Sense of "to find out the secret action or character of" is from 1580s. Meaning "discover, find out, ascertain" is from 1756. Related: Detected; detecting.