The Collaborative International Dictionary of English v.0.48:

Crowd \Crowd\ (kroud), v. t. [imp. & p. p. Crowded; p. pr. &
   vb. n. Crowding.] [OE. crouden, cruden, AS. cr[=u]dan; cf.
   D. kruijen to push in a wheelbarrow.]
   1. To push, to press, to shove. --Chaucer.
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   2. To press or drive together; to mass together. "Crowd us
      and crush us." --Shak.
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   3. To fill by pressing or thronging together; hence, to
      encumber by excess of numbers or quantity.
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            The balconies and verandas were crowded with
            spectators, anxious to behold their future
            sovereign.                            --Prescott.
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   4. To press by solicitation; to urge; to dun; hence, to treat
      discourteously or unreasonably. [Colloq.]
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   To crowd out, to press out; specifically, to prevent the
      publication of; as, the press of other matter crowded out
      the article.

   To crowd sail (Naut.), to carry an extraordinary amount of
      sail, with a view to accelerate the speed of a vessel; to
      carry a press of sail.
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WordNet (r) 3.0 (2006):

crowding
    n 1: a situation in which people or things are crowded together;
         "he didn't like the crowding on the beach"