Held - one's interest (7)
I believe the answer is:
gripped
'held' is the definition.
(gripping is a kind of holding)
'one's interest' is the wordplay.
I cannot really understand how this works, but
'interest' could be 'grip' (gripping is a kind of interesting) and 'grip' is located in the answer.
The remaining letters 'ped' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for gripped that I've seen before include "Seized or held firmly" , "Held fast or firmly" , "was fascinating" .)