Range is rare, however (6)
I believe the answer is:
sierra
'range' is the definition.
(sierra is a kind of range)
'is rare however' is the wordplay.
'however' is an anagram indicator.
'is'+'rare'='israre'
'israre' is an anagram of 'SIERRA'.
(Other definitions for sierra that I've seen before include "Mountain range -- code word for S" , "A range of mountains in Spain" , "Model of car from Ford" , "that Romeo is not after" , "- Nevada, Spanish mountain range" .)