All 6 Uses

forswear
in
The Taming of the Shrew
(Auto-generated)

Signior Hortensio, I have often heard Of your entire affection to Bianca; And since mine eyes are witness of her lightness, I will with you, if you be so contented, Forswear Bianca and her love for ever.†
Scene 4.2
Signior Lucentio, Here is my hand, and here I firmly vow Never to woo her more, but do forswear her, As one unworthy all the former favours That I have fondly flatter'd her withal.†
Scene 4.2
Would all the world but he had quite forsworn!†
Scene 4.2
Nay, I have ta'en you napping, gentle love, And have forsworn you with Hortensio.†
Scene 4.2
have you both forsworn me?
Scene 4.2 *

forsworn = renounced
we are spoiled; and yonder he is: deny him, forswear him, or else we are all undone.†
Scene 5.1

Definitions:

(1) (forswear as in: forswear my country of birth)
to decide to stop doing something; or to renounce or disavow something
(2) (meaning too rare to warrant focus)
More rarely (especially in the UK), forswear can also mean to commit perjury.