said of fabric or rope: to become worn, esp to start showing loose ragged threads at the edges
to separate the threads at the edge of (e.g. fabric)
said esp of a person's temper or nerves: to become strained so that one has difficulty maintaining self-control
to separate the threads at the edge of (e.g. fabric)
to strain or irritate (the temper or nerves)
[early French froyer, frayer to rub, from Latin fricare]