Continuous striving for money and power beginning to rankle a bit (3,4)
I believe the answer is:
rat race
'continuous striving for money and power' is the definition.
I can't judge whether this defines the answer.
'beginning to rankle a bit' is the wordplay.
'beginning to' says to take the initial letters.
'bit' becomes 'trace' (both mean a small amount).
The first letter of 'rankle' is 'r'.
'r'+'a'+'trace'='RAT-RACE'
Can you help me to learn more?
(Other definitions for rat race that I've seen before include "Competitive routine with no time to relax" , "Competitive struggle for wealth or power" , "constant effort to get ahead" , "Life's competition" , "The struggle for survival" .)