Relative of lepidopteran, in more pretentious circles (11)
I believe the answer is:
grandmother
'relative' is the definition.
(I know that grandmother is a type of relative)
'lepidopteran in more pretentious circles' is the wordplay.
'lepidopteran' becomes 'moth' (moth is a kind of lepidopteran).
'in' is an insertion indicator.
'more pretentious circles' becomes 'grander' (I am not sure about this - if you are sure you should believe this answer much more).
'moth' put inside 'grander' is 'GRANDMOTHER'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for grandmother that I've seen before include "Relation" , "Older relative" , "Proverbially competent egg sucker" , "Mum's mum" , "See 22" .)