Meaning: Finish completely
Example: They FINISHED OFF all the chocolates and had to go to the all-night garage to buy some more.
Meaning: Kill a person or animal, often when they have already been hurt
Example: The animal was badly hurt, so they FINISHED it OFF to end its suffering.
Meaning: Beat, make victory certain in sport
Example: The second goal FINISHED them OFF.
Meaning: Consume all
Example: We FINISHED OFF the coffee and had to get some more.