Chaucerian figure working during holiday period (8)
I believe the answer is:
summoner
'chaucerian figure' is the definition.
The definition suggests a singular noun which matches the answer.
'working during holiday period' is the wordplay.
'working' becomes 'on' (e.g. a machine is working or on).
'during' is an insertion indicator.
'holiday period' becomes 'summer' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'on' placed into 'summer' is 'SUMMONER'.
Can you help me to learn more?
(Other definitions for summoner that I've seen before include "Chaucerian court official" , "[PILGRIM in the CANTERBURY TALES]" .)