Though this phrase has become a regular reference, it was originally spoken by the character Juliet to Romeo in the classic Shakespeare tragedie Romeo and Juliet.

In the story, the two lovers are forced to have a relationship in secret because of an ongoing feud separating the Montegues and Capulets, their two families, in a war of hatred and scorn. Juliet is commenting on how ridiculous it is that their mere names should keep them apart despite the true love they've found in one another.

She makes the heartfelt promise that she would gladly denounce her family lineage and deny her surname would it allow them to stay together. 'What's in a name?' She says, followed by this eloquent analogy.