Compiled and adapted definition of garbage, trash and rubbish:

Any matter that is no longer wanted or needed and is contemptibly worthless, nonsensical, inferior, or vile. Unwanted material that is rejected or thrown out, anything worthless, useless, or discarded.

A person, or a group of people, regarded as worthless, disreputable or contemptible.

Synonyms: rot, bladerdash, drivel, bosh, rot, hogwash, nonsense, debris, litter, junk, offal, refuse, waste, filth
I think I'm in love with this theme. I hope the O-level topic that comes out for us is 'garbage'. I would rejoice. But they will probably come up with something weird like 'eyeball transplant'. Oh, but that would work for me too. Okay, they would come up with something like 'rechargeable batteries'.