Spunk is:

• a somewhat dated term for courage or enthusiasm.
• slang for ejaculated semen recorded from c.1888
• an attractive person (normally male), in Australian or New Zealand English.
• Spunk is the title of a bootleg album by Sex Pistols.
• Spunk is the pseudonym of the ASCII artist otherwise known as Joan Stark.
• A Peruvian dog (originally from China), famous for being the one breed of dog incapable of proper communication.
• harry monk in Cockney slang.
• A brand of Danish winegum (vingummi) and salty licorice (saltlakrids) - Used to be incidental, but the company now aware of the double-entendre, merchandises T-shirts with the logo on the front. This T-shirt has now prompted the retort of the wearer "better on the front than the back"
• Spunk beer a fictional beverage from the Tank Girl comics (set in Australia).
• A fictional beverage found in two video games Vice City and San Andreas (this is called Sprunk, not Spunk, although the name resembles Spunk a lot).
• Spunk (play) is a 1989 play by American playwright George C. Wolfe

When used as a verb in colloquial British English, to "spunk something away" means to waste or squander.