Intimidated, we tucked into fish (5)
I believe the answer is:
cowed
'intimidated' is the definition.
(synonyms)
'we tucked into fish' is the wordplay.
'tucked into' indicates putting letters inside.
'fish' becomes 'cod' (type of fish).
'we' put inside 'cod' is 'COWED'.
(Other definitions for cowed that I've seen before include "Intimidated, subdued" , "Subdued in bovine way?" , "Overawed" , "Subdued, kept under" , "Browbeaten" .)