To love, on
the Aristotelian-Thomistic analysis, is essentially to will the good of another.
Of course, there’s more to be said.
Aquinas elaborates as follows:
As the Philosopher says (Rhet. ii,
4), “to love is to wish good to someone.” Hence the movement of love has a twofold
tendency: towards the good which a man wishes to someone (to himself or to
another) and towards that to which he wishes some good. Accordingly, man has love of concupiscence
towards the good that he wishes to another, and love of friendship towards him
to whom he wishes good.