One keeps pride in check, changing into more pathetic clothes (4-5)
I believe the answer is:
'one keeps pride in check' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'changing into more pathetic clothes' is the wordplay.
'changing' indicates anagramming the letters.
'more pathetic' becomes 'lamer'.
'clothes' is an insertion indicator (some letters clothe or cover others).
'into' anagrammed gives 'iont'.
'iont' inserted inside 'lamer' is 'LION-TAMER'.
Can you help me to learn more?
(Other definitions for lion-tamer that I've seen before include "Circus entertainer" , "Circus performer" .)