Given a hard time about, in that case (4)
I believe the answer is:
then
'in that case' is the definition.
(synonyms)
'given a hard time' is the wordplay.
I cannot really see how this works, but
'hard' could be 'h' (abbreviation used in pencil classifications) and 'h' is found within the answer.
'time' could be 'ten' (I've seen this before) and 'ten' is found in the leftover letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'about' is the link.
Can you help me to learn more?
(Other definitions for then that I've seen before include "soon?" , "Afterwards - as a result" , "Once upon a time" , "At that time; next" , "Consequently" .)