darebuster
A title, intended as an insult, assigned to an individual who chooses to opt out of a mandated dare, or double-dare, or double-dog-dare, etc.
Adam: "Hey Dude, I dare you to jump off this bridge."
Nik: "Nah Dude. It's too high."
Adam: "Wow! You are such a darebuster."
Nik: "Nah Dude. It's too high."
Adam: "Wow! You are such a darebuster."