Plague - about to flee? Not entirely a sign of stupidity (6,3)
I believe the answer is:
dunces cap
'a sign of stupidity' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'plague about to flee? not entirely' is the wordplay.
'plague about' becomes 'dunc' (I can't justify this - if you can you should believe this answer much more).
'to flee?' becomes 'escape' (escaping is a kind of fleeing).
'not entirely' means to remove the last letter (not all of the word).
'escape' with its last letter removed is 'escap'.
'dunc'+'escap'='DUNCES CAP'
Can you help me to learn more?
(Other definitions for dunces cap that I've seen before include "Ignorant boy's headgear" , "Classroom idiot's headgear" , "Headgear used to humiliate slow learners" .)