The Collaborative International Dictionary of English v.0.48:

Tidal \Tid"al\, a.
   Of or pertaining to tides; caused by tides; having tides;
   periodically rising and falling, or following and ebbing; as,
   tidal waters.
   [1913 Webster]

         The tidal wave of deeper souls
         Into our inmost being rolls,
         And lifts us unawares
         Out of all meaner cares.                 --Longfellow.
   [1913 Webster]

   Tidal air (Physiol.), the air which passes in and out of
      the lungs in ordinary breathing. It varies from twenty to
      thirty cubic inches.

   Tidal basin, a dock that is filled at the rising of the
      tide.

   Tidal wave.
   (a) See Tide wave, under Tide. Cf. 4th Bore.
   (b) A vast, swift wave caused by an earthquake or some
       extraordinary combination of natural causes. It rises far
       above high-water mark and is often very destructive upon
       low-lying coasts.
       [1913 Webster]

WordNet (r) 3.0 (2006):

tidal basin
    n 1: a basin that is full of water at high tide