The reason that the title of "The Love Song of J. Alfred Prufrock" by T. S. Eliot includes the words "love song" is that the situation of the poem is typical of the genre of love song. The narrator intends to propose to or proposition his beloved, but is worried about rejection:
Would it have been worth while
If one, settling a pillow or throwing off a shawl,
..., should say:
"That is not it at all,
That is not what I meant, at all."
Although the basic situation is that of a classic love song, what is different is the nature of the narrator (shy, retiring, middle-aged, inarticulate) and the background of urban modernity, in which the old certainties (and old literary genres) are breaking down, leading to the problem of the failure of the lovers ton make meaning and communicate.