Skill fixing fence, if icy (10)
I believe the answer is:
efficiency
'skill' is the definition.
(thesaurus)
'fixing fence if icy' is the wordplay.
'fixing' indicates anagramming the letters.
'fence'+'if'+'icy'='fenceificy'
'fenceificy' anagrammed gives 'EFFICIENCY'.
(Other definitions for efficiency that I've seen before include "State of working with minimum wasted effort" , "Performance with speed and economy" , "Economy in production" .)