Offer coloured bag up (6)
I believe the answer is:
tender
'offer' is the definition.
(tender can mean to offer something)
'coloured bag up' is the wordplay.
'coloured' becomes 'red' (similar in meaning).
'bag' becomes 'net' (I've seen this in other clues).
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'red'+'net'='rednet'
'rednet' backwards is 'TENDER'.
(Other definitions for tender that I've seen before include "not needing good teeth" , "Easily chewed" , "Romantic" , "Painful when touched" , "Make formal offer" .)