Search Result for "metastable": 
Wordnet 3.0

ADJECTIVE (1)

1. (of physical systems) continuing in its present state of equilibrium unless sufficiently disturbed to pass to a more stable state of equilibrium; 



WordNet (r) 3.0 (2006):

metastable
    adj 1: (of physical systems) continuing in its present state of
           equilibrium unless sufficiently disturbed to pass to a
           more stable state of equilibrium