An eccentric; weirdo.
Something that is different from others in the same category; odd one out.
Someone who lacks a partner or team.
A temporary crew member who joins a mission with an established crew.
One who behaves in a crazy manner.
A pitch thrown with added pressure by the index finger and a twisting wrist motion resulting in a motion to the right when thrown by a right-handed pitcher.
Crazy, offbeat, bizarre, zany, or weird.