1.PrepositionWilling to participate in; interested in.
"Are you up for a trip to the library today?"
2.PrepositionBeing or due to be evaluated, inspected, judged, considered, sold, etc., in the stated circumstances or by the stated method.
"He is up for reelection next year, so he will try to control his image.; He is up for second degree murder.; It's still up for debate.; She put her jewelry up for auction.; My car is up for sale."