(verb)
to rub or gnaw on something and cause it to gradually wear away, or to form something by such a problem;
e.g. The straps of the device fret against the moving parts and get thinned out. The flowing waters were able to fret a channel for themselves and form a stream.
(verb)
to ripple or agitate some surface, to move or flow in small waves;
e.g. The stones in the lake fret its water and cause it to ripple.
(noun)
an ornamental design that consists of horizontal and vertical lines and that is typically repeated on some piece of art or architecture;
e.g. He sketched out the fret that he wanted to carve into the walls.
(verb)
to decorate something with repetitions of an ornamental design consisting of horizontal and vertical lines;
e.g. The workers carved day and night to fret the columns of the building.
(noun)
each of the ridges found on the fingerboard of some stringed musical instruments (e.g. the guitar), used to define the positioning of the fingers for playing the desired notes;
e.g. Your finger should be at the third fret to play this note.
(verb)
to fit the fingerboard of a stringed musical instrument with ridges to define the positioning of the fingers, or to press the string of such an instrument against such a ridge in order to play a note;
e.g. This process is the most efficient way to fret a banjo. You have to fret the fifth string to play this note.