1. Materials, equipment, supplies, components: Janet has the stuff that she needs to make the rug.

Someone has said that hope is the stuff that dreams are made of.

2. Things, belongings; possessions or a pile of things: Michael left his stuff in his Mother's attic when he moved to his new job in another state.
3. Something that doesn't have a specific name: The stuff that Elva says about Norbert is simply not true.

1. To pile up, to fill, to cram, to load, or to heap: Irene stuffed the trunk with her winter clothes.

Kelsey stuffed the cushions with down or small soft feathers.

Maude stuffed herself with chocolate candy.

2. To fill the skin of a dead animal so it looks the way it did when it was living: For some people, it seems barbaric to stuff animals for decorative reasons.
3. To load or to jam in: Grace said, "Kermit, just stuff the laundry into the washing machine, put in the soap, and then turn the machine on."