Wordnet 3.0
ADJECTIVE (1)
1. 
 constructed so as to tip up or out of the way; 
- Example: "the little tip-up seat of the taxi"
The Collaborative International Dictionary of English v.0.48:
Tip-up \Tip"-up`\, n. (Zool.)
   The spotted sandpiper; -- called also teeter-tail. See
   under Sandpiper.
   [1913 Webster]
The Collaborative International Dictionary of English v.0.48:
collapsible \collapsible\ adj.
   Capable of collapsing or being collapsed; as, a collapsible
   boat. [Narrower terms: telescopic; tip-up] Also See:
   folded. Antonym: noncollapsible.
   Syn: collapsable.
        [WordNet 1.5]
WordNet (r) 3.0 (2006):
tip-up
    adj 1: constructed so as to tip up or out of the way; "the
           little tip-up seat of the taxi"