diffuser

(noun) baffle that distributes sound waves evenly. Synonyms: diffusor.

(noun) optical device that distributes the light of a lamp evenly. Synonyms: diffusor.

(adj) spread out; not concentrated in one place. Synonyms: diffuse. Example: "A large diffuse organization."

(adj) (of light) transmitted from a broad light source or reflected. Synonyms: soft (vs. hard), diffuse, diffused.

(adj) lacking conciseness. Synonyms: diffuse. Example: "A diffuse historical novel."