The low fellow proposed! (6)
I believe the answer is:
mooted
'proposed' is the definition.
(I've seen this before)
'the low fellow' is the wordplay.
'the low' becomes 'moo' (both can mean to make a cow noise).
'fellow' becomes 'ted' (I've seen this in other clues).
'moo'+'ted'='MOOTED'
(Other definitions for mooted that I've seen before include "'Debated, considered (6)'" , "Raised matter for discussion" , "Proposed for discussion" , "Raised question for discussion" .)