push off

verb

1. Also: push out. to move into open water, as by being cast off from a mooring

2. informal,  (intr) to go away; leave

Idioms and Phrases

Also, shove off. Leave, set out, depart, as in The patrol pushed off before dawn, or It's time to shove off. This usage alludes to the literal meaning of a person in a boat pushing against the bank or dock to move away from the shore. [Colloquial; early 1900s]