The Collaborative International Dictionary of English v.0.48:

Oar \Oar\ ([=o]r), n [AS. [=a]r; akin to Icel. [=a]r, Dan. aare,
   Sw. [*a]ra; perh. akin to E. row, v. Cf. Rowlock.]
   [1913 Webster]
   1. An implement for impelling a boat, being a slender piece
      of timber, usually ash or spruce, with a grip or handle at
      one end and a broad blade at the other. The part which
      rests in the rowlock is called the loom.
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   Note: An oar is a kind of long paddle, which swings about a
         kind of fulcrum, called a rowlock, fixed to the side of
         the boat.
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   2. An oarsman; a rower; as, he is a good oar.
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   3. (Zool.) An oarlike swimming organ of various
      invertebrates.
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   Oar cock
      (Zool.), the water rail. [Prov. Eng.]

   Spoon oar, an oar having the blade so curved as to afford a
      better hold upon the water in rowing.

   To boat the oars, to cease rowing, and lay the oars in the
      boat.

   To feather the oars. See under Feather., v. t.

   To lie on the oars, to cease pulling, raising the oars out
      of water, but not boating them; to cease from work of any
      kind; to be idle; to rest.

   To muffle the oars, to put something round that part which
      rests in the rowlock, to prevent noise in rowing.

   To put in one's oar, to give aid or advice; -- commonly
      used of a person who obtrudes aid or counsel not invited.


   To ship the oars, to place them in the rowlocks.

   To toss the oars, To peak the oars, to lift them from the
      rowlocks and hold them perpendicularly, the handle resting
      on the bottom of the boat.

   To trail oars, to allow them to trail in the water
      alongside of the boat.

   To unship the oars, to take them out of the rowlocks.
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The Collaborative International Dictionary of English v.0.48:

Boat \Boat\ (b[=o]t), v. t. [imp. & p. p. Boated; p. pr. & vb.
   n. Boating.]
   1. To transport in a boat; as, to boat goods.
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   2. To place in a boat; as, to boat oars.
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   To boat the oars. See under Oar.
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