Bored languor will make some of the children nuisances (5)
I believe the answer is:
ennui
'bored languor' is the definition.
'ennui' can be an answer for 'languor' (I've seen this before). I'm not sure about the 'bored' bit.
'some of the children nuisances' is the wordplay.
'some of' says the answer is hidden in the clue.
'ENNUI' can be found hidden inside 'children nuisances'.
'will make' acts as a link.
Can you help me to learn more?
(Other definitions for ennui that I've seen before include "Feeling of listlessness" , "depression" , "Bored listlessness" , "Low interest rate" , "to make one list less when connected" .)