Greenhorn
A greenhorn, or simply to be green, was a term applied to a beginner who was said to be inexperienced and therefore incompetent at the task set before them.

In 2267, after DeSalle suggested Pavel Chekov might need to seek help in order to re-calibrate his sensors, the ensign retorted, "I can do it, sir. I'm not that green." ()

Later that year, after Commodore Stocker took over command of the  and drove it through the Romulan Neutral Zone, the senile Captain James T. Kirk complained about Stocker as the "Greenhorn, up there ruining my ship." ()

In 2374, Tom Paris described Harry Kim's level of ness upon first joining the crew of  as "deep, almost fluorescent green." ()

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