Tum·bling a. & vb. n. from Tumble, v.
  Tumbling barrel. Same as Rumble, n., 4.
  Tumbling bay, an overfall, or weir, in a canal.
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  Tum·ble v. i. [imp. & p. p. Tumbled p. pr. & vb. n. Tumbling ]
  1. To roll over, or to and fro; to throw one's self about; as, a person in pain tumbles and tosses.
  2. To roll down; to fall suddenly and violently; to be precipitated; as, to tumble from a scaffold.
     He who tumbles from a tower surely has a greater blow than he who slides from a molehill.   --South.
  3. To play tricks by various movements and contortions of the body; to perform the feats of an acrobat.
  To tumble home Naut., to incline inward, as the sides of a vessel, above the bends or extreme breadth; -- used esp. in the phrase tumbling home.  Cf. Wall-sided.
  tumbling
       adj 1: moving in surges and billows and rolls; "billowing smoke
              from burning houses"; "the rolling fog"; "the rolling
              sea"; "the tumbling water of the rapids" [syn: billowing,
               rolling]
       2: pitching headlong with a rolling or twisting movement; "a
          violent tumbling fall"
       n : the gymnastic moves of an acrobat [syn: acrobatics]