Egyptian banker stealing pennies is bit of a tit (6)
I believe the answer is:
nipple
'is bit of a tit' is the definition.
(part of a breast)
'egyptian banker stealing pennies' is the wordplay.
'egyptian banker' becomes 'Nile' (Egyptian river, something with banks).
'stealing' means one lot of letters goes inside another.
'pennies' becomes 'pp' (two instances of the abbreviation for penny).
'nile' going around 'pp' is 'NIPPLE'.
(Other definitions for nipple that I've seen before include "private area" , "flow regulator" , "Oil supplier" , "Chest projection" , "Source of mother's milk" .)