Origin: 1325–75 for earlier sense “referee, arbiter”; 1560–70 for current sense; ME < L: one who composes, equiv. to composi-, var. s. of compōnere (see component, composite) + -tor-tor
com·pos·i·tor (kəm-pŏz'ĭ-tər) n. One that sets written material into type; a typesetter.
[Middle English compositur, one who composes, settler of disputes, from Anglo-Norman compositour, from Latin, writer, compiler, from compōnere, composit-, to put together; see component.] com·pos'i·to'ri·al (-tôr'ē-əl, -tōr'-) adj.