The Collaborative International Dictionary of English v.0.48:

Aboard \A*board"\, adv. [Pref. a- on, in + board.]
   1. On board; into or within a ship or boat; hence, into or
      within a railway car.
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   2. Alongside; as, close aboard.
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   To fall aboard of, to strike a ship's side; to fall foul
      of.

   To haul the tacks aboard, to set the courses.

   To keep the land aboard, to hug the shore.

   To lay (a ship) aboard, to place one's own ship close
      alongside of (a ship) for fighting.
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The Collaborative International Dictionary of English v.0.48:

Tack \Tack\, n. [OE. tak, takke, a fastening; akin to D. tak a
   branch, twig, G. zacke a twig, prong, spike, Dan. takke a
   tack, spike; cf. also Sw. tagg prickle, point, Icel. t[=a]g a
   willow twig, Ir. taca a peg, nail, fastening, Gael. tacaid,
   Armor. & Corn. tach; perhaps akin to E. take. Cf. Attach,
   Attack, Detach, Tag an end, Zigzag.]
   1. A small, short, sharp-pointed nail, usually having a
      broad, flat head.
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   2. That which is attached; a supplement; an appendix. See
      Tack, v. t., 3. --Macaulay.
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            Some tacks had been made to money bills in King
            Charles's time.                       --Bp. Burnet.
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   3. (Naut.)
      (a) A rope used to hold in place the foremost lower
          corners of the courses when the vessel is closehauled
          (see Illust. of Ship); also, a rope employed to pull
          the lower corner of a studding sail to the boom.
      (b) The part of a sail to which the tack is usually
          fastened; the foremost lower corner of fore-and-aft
          sails, as of schooners (see Illust. of Sail).
      (c) The direction of a vessel in regard to the trim of her
          sails; as, the starboard tack, or port tack; -- the
          former when she is closehauled with the wind on her
          starboard side; hence, the run of a vessel on one
          tack; also, a change of direction; as, to take a
          different tack; -- often used metaphorically.
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   4. (Scots Law) A contract by which the use of a thing is set,
      or let, for hire; a lease. --Burrill.
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   5. Confidence; reliance. [Prov. Eng.] --Halliwell.
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   Tack of a flag (Naut.), a line spliced into the eye at the
      foot of the hoist for securing the flag to the halyards.


   Tack pins (Naut.), belaying pins; -- also called jack
      pins.

   To haul the tacks aboard (Naut.), to set the courses.

   To hold tack, to last or hold out. --Milton.
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