What does "poop" mean?

Additional senses

1. 2.To make a noise; to pop; also, to break wind.
2. 3.A deck raised above the after part of a vessel; the hindmost or after part of a vessel's hull; also, a cabin covered by such a deck. See Poop deck, under Deck. See also Roundhouse. With wind in poop, the vessel plows the sea. Dryden. The poop was beaten gold. Shak.
3. 4.(a) To break over the poop or stern, as a wave. "A sea which he thought was going to poop her." Lord Dufferin. (b) To strike in the stern, as by collision.