Theme
Part of speech: noun
Definition: a subject of a talk or an artistic piece; a topic. a recurring idea; a motif. the main melody of a piece of music, especially one that is the source of variations. The collection of color schemes, sounds, artwork etc., that "skin" an environment towards a particular motif. stem of a word thematic relation of a noun phrase to a verb theta role in generative grammar and government and binding theory. topic, what is being talked about, as opposed to rheme
Example sentence: If there's one theme in all my work, it's about authenticity and self-expression. It's the idea that some things are, in some real sense, really you - or express what you and others aren't.
Motif
Part of speech: noun
Definition: A recurring or dominant element; a theme.A short melodic passage that is repeated in several parts of a workA decorative figure that is repeated in a designcrystallography: The physical object or objects repeated at each point of a lattice. Usually atoms or molecules.