Definition of long-armed:
(adj) :
Having much distance in space from one end to the other.
(adj) :
Specifically, having much distance in a horizontal dimension (see also Usage Notes below).
(adj) :
Travelling a great distance.
(adj) :
(informal) Having a long penis.
(adj) :
Travelling or extending too great a distance in space.
(adj) :
(of weapons fire, landing aircraft, etc.) Passing or landing ahead of or beyond the intended target or location.