Lithe ibex fell tragically (8)
I believe the answer is:
flexible
'lithe' is the definition.
(I've seen this before)
'ibex fell tragically' is the wordplay.
'tragically' is an anagram indicator (I've seen this in other clues).
'ibex'+'fell'='ibexfell'
'ibexfell' is an anagram of 'FLEXIBLE'.
(Other definitions for flexible that I've seen before include "Able to bend without breaking" , "Accommodating" , "Not rigid" , "Bending easily" , "Not hard" .)