A protest losing its leader - that's humbling (6)
I believe the answer is:
abject
'humbling' is the definition.
Both the answer and definition are adjectives. Perhaps they are linked in a way I don't understand?
'a protest losing its leader' is the wordplay.
'protest' becomes 'object' (as in objecting to something).
'losing its leader' means to remove the first letter.
'object' with its first letter taken off is 'bject'.
'a'+'bject'='ABJECT'
'that's' is the link.
Can you help me to learn more?
(Other definitions for abject that I've seen before include "feeble" , "Lacking all pride, like a humble apology" , "Deeply miserable" , "woeful" , "'Grovelling, apology say (6)'" .)