Thought to be an alteration of recruit + -ie, or from rook (“a cheat”) + -ie. Another possible origin is Dutch broekie (short for broekvent (“a boy still in short trousers”)), a common term for a shipmate.
rookie (plural rookies)
- An inexperienced recruit, especially in the police or armed forces.
- A novice.
- An athlete either new to the sport or to a team or in his first year of professional competition, especially said of baseball, basketball, hockey and American football players.
- (Britain) A type of firecracker, used by farmers to scare rooks.
an inexperienced recruit
- non-professional; amateur
- The game was going well until I made that rookie mistake.
- the rookiest of rookie mistakes
amateur — see amateur