Synonyms for Polish Off (same or very similar meaning)
WordNet sense 1 (kill intentionally and with premeditation):
dispatch, hit, murder, off, remove, slay, bump off
WordNet sense 2 (finish eating all the food on one's plate or on the table):
finish, eat up
WordNet sense 3 (finish a task completely):
clear up, get through, finish up, finish off, mop up, wrap up
From the ODE community, based on WordNet
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