Stocky is a synonym of bulky.
As adjectives the difference between bulky and stocky
is that bulky is being large in size, mass, or volume while stocky is sturdy; solidly built; heavy and compact.
bulky
English
Adjective
(er)
Being large in size, mass, or volume.
Unwieldy
(bodybuilding) Having excess body mass, especially muscle.
stocky
English
Adjective
(er)
(of a person or an animal) sturdy; solidly built; heavy and compact