old hand
noun phrase

- a person who is very experienced
(Cambridge Dictionary)

Every company has an old hand (and not just one) who seems to know everything and everybody and how things work. No company can function without old hands. It's a key success factor.

But why not call them an old head, an old arm or an old nose? That's because there was a time when most skills and trades were done with the hands, whether it was the butcher, the baker or the candlestick maker.

And for that reason the word hand, in addition to meaning one of the most important body parts, eventually developed the sense of an experienced person. By adding the adjective "old," the expression then refers to someone who boasts long years of experience.

The word hand has additional meanings that may not be familiar to some non-native English speakers:

- one of the long, thin pieces that point to the numbers on a clock or watch (The second hand on my watch stopped working)

- the set of cards that a player has in a game, which are usually described as being good or bad depending on the cards one is dealt (I have a horrible hand this game!)

- help (Can you give me a hand with this table? It's really heavy)

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SYNONYMS

expert, old timer, long timer, old guard, old school, old soldier, pro, vet, veteran, warhorse

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SMUGGLE OWAD into today's conversation

"Call Charlie if you get any IT problems. He's an old hand with anything to do with computers."