Source : Webster's Revised Unabridged Dictionary (1913)

Tip-up \Tip"-up`\, n. (Zo["o]l.)
   The spotted sandpiper; -- called also {teeter-tail}. See
   under {Sandpiper}.

Source : WordNet®

tip-up
     adj : constructed so as to tip up or out of the way; "the little
           tip-up seat of the taxi"