Within the context of the poem itself, Belinda is the only name given. But, Belinda the character is named for a real person: Arabella Fermor. "The Rape of the Lock" is a mock epic poem (or, as Pope refers to it, "an Heroi-Comical Poem"). The poem satirizes an actual account involving two aristocratic families. Pope's friend John Caryll suggested Pope write the mock epic to shed some levity on the quarrel that resulted from the event when Lord Petre cut a lock of hair from Arabella Fermor. The first few lines of the poem address Caryll and note that the poem is told in heroic/epic style but the subject matter is trivial or "slight":
I sing--This verse to Caryll, Muse! is due:
This, even Belinda may vouchsafe to view:
Slight is the subject, but not so the praise,
If she inspire, and he approve my lays. (3-6)
In the second edition of the poem, Pope added a letter addressed to Mrs. Arabella Fermor, detailing his reasons for writing the poem. "The human persons are as fictitious as the airy ones; and the character of Belinda, as it is now managed, resembles you in nothing but in beauty."
Additionally, though Belinda is never fully named in the text of the poem, she does have a brother in the story--Sir Plume. Therefore, it could be deduced that Plume is her last name, too, though this is never explicitly stated as fact.