Eastern variety of miner moth (6)
I believe the answer is:
ermine
'moth' is the definition.
(type of moth)
'eastern variety of miner' is the wordplay.
'eastern' becomes 'e'.
'variety of' is an anagram indicator.
'miner' with letters rearranged gives 'rmine'.
'e'+'rmine'='ERMINE'
(Other definitions for ermine that I've seen before include "Stoat's winter fur" , "Warm white covering" , "Fur for an English judge" , "special trimmings" , "Fur-bearing mammal" .)