Glue on strap to provide extra strength (13)
I believe the answer is:
reinforcement
'extra strength' is the definition.
The answer and definition can be both related to thinking as well as being singular nouns.
Maybe there's an association between them I don't understand?
'glue on strap to' is the wordplay.
I cannot really see how this works, but
'glue' could be 'cement' (I've seen this in another clue) and 'cement' is present in the answer.
'on' could be 're' ('on' can be mean 'with reference to') and 're' is present in the answer.
'to' could be 'for' and 'for' is found within the answer.
The remaining letters 'in' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'provide' is the link.
Can you help me to learn more?
(Other definitions for reinforcement that I've seen before include "Augmentation" , "Back-up" , "Strengthening" , "supporting structure" , "More support needed" .)