Summon by a gesture (6)
I believe the answer is:
beckon
'summon by a gesture' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for beckon that I've seen before include "Summon with finger gesture" , "Summon by sign" , "Gesture to approach" , "Make signs to summon" , "Gesture closer" .)