Hum (7)
I believe the answer is:
vibrate
(Other definitions for vibrate that I've seen before include "Shake, quiver, or throb" , "tremble" , "Quiver rapidly, resonate" , "Move rapidly to and fro" , "swing" .)
I believe the answer is:
vibrate
(Other definitions for vibrate that I've seen before include "Shake, quiver, or throb" , "tremble" , "Quiver rapidly, resonate" , "Move rapidly to and fro" , "swing" .)