Tempted by a bit of luck on the red (5)
I believe the answer is:
lured
'tempted' is the definition.
('lure' can be a synonym of 'tempt')
'by a bit of luck on the red' is the wordplay.
'by a' becomes 'u' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'bit of' indicates taking the first letters.
'on' is a charade indicator (letters next to each other).
The first letter of 'luck' is 'l'.
'u' after 'l' is 'lu'.
'lu'+'red'='LURED'
Can you help me to learn more?
(Other definitions for lured that I've seen before include "Seduced" , "was enticing" , "Tempted or enticed" , "Attracted" .)