The Collaborative International Dictionary of English v.0.48:

poo \poo\, poop \poop\, poopoo \poopoo\n.
   Excrement; feces; -- informal baby talk sometimes used as a
   euphemism. [slang]
   [PJC]

The Collaborative International Dictionary of English v.0.48:

Poop \Poop\, n. [F. poupe; cf. Sp. & Pg. popa, It. poppa; all
   fr. L. puppis.] (Naut.)
   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.
   [1913 Webster]

         With wind in poop, the vessel plows the sea. --Dryden.
   [1913 Webster]

         The poop was beaten gold.                --Shak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Poop \Poop\, v. t. (Naut.)
   (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.
       [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Poop \Poop\, n. (Arch.)
   See 2d Poppy.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Poop \Poop\, v. i. [imp. & p. p. Pooped; p. pr. & vb. n.
   Pooping.] [Cf. D. poepen. See Pop.]
   To make a noise; to pop; also, to break wind.
   [1913 Webster]