It's not, it was a term coined by two marxist sociologists: Barbara Fredrickson and Tomi-Ann Roberts.

But even then it's more retarded in this context since Harley Quinn is a fictional character...

Objectification certainly does exist: In Vietnam, when leading generals were discussing strategies that involved gassing their own troops, acceptable losses and whatnot, that was reducing the men involved into merely active objects.

Objectification of women, though, not nearly so common. For they are viewed as so inherently valuable, that an active effort to reduce that perception is still giving special consideration.

Just like gaslighting.