verb / noun
fret
FRET/fret/
To wear away through persistent irritation.
The loose metal parts fret against each other as they vibrate.

Etymology
The old meaning 'devour' suggests emotions consuming the heart or mind. The anxiety sense may come from this image or from rubbing and wearing away; it later came to mean worrying oneself.
In context
Don't worry, don't worry, do not fret, [laughs] I'm not going to evict you.
More examples
- Constant rubbing has fretted a groove in the wooden post.
- Salt water frets away the exposed metal.
- The moving chain frets a narrow groove in the wooden rail.
Forms
fret · frets · fretted · fretting