theme (Noun) — The thing or area being discussed. ex. "his letters were always on the theme of love"
theme (Noun) — A unifying idea that is a recurrent element in literary or artistic work. ex. "it was the usual 'boy gets girl' theme"
theme (Noun) — (music) melodic subject of a musical composition. ex. "the theme is announced in the first measures" ex. "the melodic theme is announced in the first measures" ex. "the musical theme is announced in the first measures"
theme (Noun) — An essay (especially one written as an assignment). ex. "he got an A on his theme"
theme (Noun) — (linguistics) the form of a word after all affixes are removed. ex. "thematic vowels are part of the theme"
theme (Noun) — (computing) a collection of colour schemes, sounds, artwork, etc, used in the interface of a computer program, usually interchangeably.
theme (Verb) — Provide with a particular theme or motive. ex. "the restaurant often themes its menus"