Working at the bank is informative (7)
I believe the answer is:
telling
'informative' is the definition.
(similar in meaning)
'working at the bank' is the wordplay.
I cannot quite see how this works, but
'at' could be 'in' (synonymous in some cases - eg at school, in school) and 'in' is found within the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
This explanation may well be incorrect...
'is' acts as a link.
Can you help me to learn more?
(Other definitions for telling that I've seen before include "Powerful; relating" , "Providing information" , "relation" , "influential" , "Counting" .)