fit as a fiddle
common saying

- to be very healthy and strong

(Cambridge Dictionaries)

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ORIGIN

As a noun, fiddle is an informal term for a violin. It stems from the Old English fiðele and evolved via several variations including fithele and fedele. While fiddle is related to words in other languages (Dutch vedel, German Fiedel), the exact origin is unknown.

One suggestion is that it came from the Medieval Latin "vitula," meaning stringed instrument, which in turn may be related to the Latin "vitularia" (to celebrate joyfully) and Vitula, the Roman goddess of joy and victory.

The expression "fit as a fiddle" is an example of a simile, an expression comparing one thing with another and always including the words "as" or "like." Why being physically fit is comparable with the fiddle is not clear.

Perhaps it derives from the idea that musical instruments must be properly maintained and kept in good shape for optimal sound. That still does not explain why the fiddle would be chosen as opposed to the flute, clarinet, drum or tuba, other than the fact that stringed instruments generally require more tuning. In any case, it creates a nice alliteration.

Fiddle is also a chiefly British term that describes an act of defrauding or cheating (The bank experienced a major credit card fiddle), or a small task that seems unnecessarily complex or awkward (Refilling the copy machine with paper is a real fiddle).

When used as a verb, fiddle means to touch or fidget with something in a nervous way (Stop fiddling with your pencil!), as well as to tinker with something in an attempt to make a minor repair or adjustment (He’s fiddling with his computer at the moment).

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SYNONYMS

able bodied, hardy, hale and hardy, healthy, hearty, in good shape, in good condition, in the pink, robust, rosey-cheeked, sound, strong, vigorous, fit, full of life, in fine feather, in fine fettle, stout

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SMUGGLE OWAD into today's conversation

"My parents are in their 80s and both are still AS FIT AS A FIDDLE."