The Collaborative International Dictionary of English v.0.48:
Ascendible \As*cend"i*ble\, a. [L. ascendibilis.] Capable of being ascended; climbable. [1913 Webster]WordNet (r) 3.0 (2006):
ascendible adj 1: capable of being ascended [syn: ascendable, ascendible, climbable]