The adjective form of testicle is testicular. The phrase should be "testicular fortitude".
I just met a guy who can't tell the difference between a noun and an adjective. It takes a lot of testicular fortitude to display your ignorance in public like that.
by My dixie wrecked November 26, 2003
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means having balls, bravery, courage
if ya wanna win, u bettah reach down and grab for sum testicle fortitude
by Inflame November 24, 2003
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