to remove things from a vehicle or ship after it has taken them somewhere

to remove the contents of something after you have finished using it

Each time a gun is laid down it must first be broken and unloaded.

to pass the responsibility for somebody/something to somebody else; to tell somebody about your problems and worries

It's his problem, not something he should unload onto you.

to get rid of or sell something, especially something illegal or of bad quality

They want to unload their shares at the right price.

LEARNit Dictionary