Gesture, motion (3)
I believe the answer is:
nod
I believe this is a double definition.
'gesture' is the first definition.
(I know that gesture is the is a more specific form of the action of nod.)
'motion' is the second definition.
(I know that motion is the is a more specific form of the action of nod.)
(Other definitions for nod that I've seen before include "Go to sleep in this land" , "overlook something" , "Cain was banished to the land of ..." , "Move head in agreement" , "Sign of assent or salutation" .)