Alternative to truth, in a party game (4)
I believe the answer is:
dare
'alternative to truth in a party game' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for dare that I've seen before include "Venture to read" , "Take the risk, face the danger" , "Challenge of courage" , "Venture, have courage" , "Take a chance - read about it" .)