What is a rookie? Where does the word come from?

A rookie is someone new to a particular situation or recently promoted to a higher level of competition or responsibility.

The word is most commonly used in American sports commentary to describe a team player in their first season - a rookie NFL quarterback, example, or a new player on the Ryder Cup team.

2014 Ryder Cup rookies 

Using a rookie in a high-pressured situation carries a risk. He/She may buckle under the new pressure or prove unable to reach the required level.

There is also a suggestion that youth and/or inexperience makes a rookie more likely to make elementary mistakes. 

Where does the word rookie come from?

The origin is uncertain but the OED suggests that it may be a corruption of the word recruit. It's first citation is from Rudyard Kipling's Barrack-Room Ballads (1892) 

So 'ark an' 'eed, you rookies, which is always grumblin' sore, referring to rookies in the sense of raw recruits to the British Army. 

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