Fret has a variety of meanings (according to Dictionary.com)  ‚Äčas both a noun and verb.

Fret, the verb

Meaning Example
To feel or express worry, annoyance, discontent, or the like.
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To cause corrosion; gnaw into something.
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To become eaten, worn, or corroded (often followed by away).
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Fret, the noun

Meaning Example
An irritated state of mind; annoyance; vexation.
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Erosion; corrosion; gnawing.
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A worn or eroded place. o become eaten, worn, or corroded.....
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