restitution - payment of some sort .....used in the book when Nirmal mentions to Kanai that since the Bay of Bengal has given so much to the Sundarbans...they need to take something back .....and hence the Bay is looking for a restitution.
androgyny - showing characteristics of both male and female....used in the book when Kanai mentions a man dressed up funnily at the railway stations.
parturition - the process of giving birth...mentioned when Kanai speaks of the Ganges giving birth to numerous islands ....
demur - raise doubts or fear.....When Piya is scared of the various boat-wallas trying to skin money of her.
obsequious - Obedient or attentive to an excessive or servile degree...initially the guard from the forest department behaved obsequiously later he became extremely officious .
bandolier - A shoulder-belt with loops or pockets for cartridges.
desultory - Lacking a plan, purpose, or enthusiasm...when Piya was searching for a boat to hire ...her process was entirely unplanned ....
mime - The theatrical technique of suggesting action, character, or emotion without words, using only gesture, expression, and movement.
pantomime - excessive mime
gesticulate - Use gestures, esp. dramatic ones, instead of speaking or to emphasize one's words