The proper term is anti-ice. De-ice is used to describe devices that destroy ice formed on the wing surface like pneumatic boots
Well, the manuals for the Boeings I flew (IIRC) said the systems could be used for anti-ice or de-ice.
As said above, rarely needed: in 13 years on the 737-200 I recall only one occasion whe we got ice on the wings. Climbing out of Malaga over the Sierra Nevada (the original one, for you chaps West of 60W) we went through some lenticular cloud at about FL200 and the climb rate dropped to zero. The wing was visible from the flight deck, and a quick burst of wing anti-ice did
de-ice it PDQ and the climb resumed. Later, on B757/767, I don't recall ever using the wing anti-ice.
FWIW