Anything light, soft or fuzzy, especially fur, hair, feathers.

Anything inconsequential or superficial.

(informal) A lapse or mistake, especially a mistake in an actor's lines.

(New England) Marshmallow creme.

(LGBT) A passive partner in a lesbian relationship.

(Australia, New Zealand, euphemistic) A fart. (Can we add an example for this sense?)

(fandom slang) Fan fiction, or part of a fan fiction, which is sweet and feel-good in tone, usually involving romance.

(UK, roleplaying games) A form of roleplaying which is inconsequential and not related to the plot; often used in the context of (but not limited to) filling time.

(transitive) To make something fluffy.

(intransitive) To become fluffy, puff up.

(intransitive) To move lightly like fluff.

(informal, transitive, intransitive, of an actor or announcer) To make a mistake in one's lines.

(informal, transitive) To do incorrectly, for example mishit, miskick, miscue etc.

(intransitive, Australia, euphemistic) To break wind, to fart.

(transitive, slang) To arouse (a male pornographic actor) before filming.