Mother East's first name (3)
I believe the answer is:
mae
'name' is the definition.
'mother east's' is the wordplay.
'mother' becomes 'ma' (Ma is another word for mother or mum).
'east' becomes 'e' (abbreviation).
'ma'+'e'='MAE'
'first' acts as a link.
(Other definitions for mae that I've seen before include "- - West, life-jacket" , "more Scots" , "- West, US film actress" , "- - West, movie vamp" , "Woman" .)