A green or inexperienced person; a novice or beginner with little experience.
Possibly a variant or dialectal form combining 'green' (meaning inexperienced, from the idea of unripe fruit) with 'uk' or '-uck' suffix, though the exact origin is obscure.
The metaphor of 'green' for inexperienced comes from unripe fruit—a green apple isn't ready yet, so a 'green' person isn't fully developed or experienced yet, which is why beginners are universally called 'greenhorns' or 'greenies.'
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