Note Indian opener caught chasing century (5)
I believe the answer is:
tonic
'note' is the definition.
(tonic is a kind of note)
'indian opener caught chasing century' is the wordplay.
'opener' suggests taking the first letters.
'caught' becomes 'c' (cricket abbreviation).
'chasing' means one lot of letters go next to another.
'century' becomes 'ton' (both can mean one hundred of something).
The initial letter of 'indian' is 'i'.
'i'+'c'='ic'
'ic' after 'ton' is 'TONIC'.
(Other definitions for tonic that I've seen before include "It goes with gin" , "Keynote of a scale" , "shot in the arm" , "requirement for invigoration?" , "Producing tension of muscles" .)