1 a subject or topic on which a person speaks, writes, or thinks.
2 Mus. a prominent or frequently recurring melody or group of notes in a composition.
3 US a school exercise, esp. an essay, on a given subject.
4 Gram. the stem of a noun or verb; the part to which inflections are added, esp. composed of the root and an added vowel.
5 hist. any of the 29 provinces in the Byzantine empire.
Phrases and idioms:
theme park an amusement park organized round a unifying idea. theme song (or tune)
1 a recurrent melody in a musical play or film.
2 a signature tune.
Etymology: ME teme ult. f. Gk thema -matos f. tithemi set, place
Useful english dictionary. 2012.