Take longer to tell (9)
I believe the answer is:
outnumber
'tell' is the definition.
Although both the answer and definition are verbs in their base form, I cannot understand how they can define each other.
'take longer' is the wordplay.
I cannot really understand how this works, but
'take' could be 'be' (being is a kind of taking) and 'be' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Other definitions for outnumber that I've seen before include "Have more (eg troops) than" , "Be too many for in contest or conflict" , "Exceed in figures" , "Be more numerous than" , "Exceed numerically" .)