A fishhook is a metal wire, barbed and bent into a U, cast at the end of a line to catch fish. It is a period charge: an early version is found in the arms of von Born, c.1370 [Gelre 41v], and later in the arms of von Angelloch, 1605 [Siebmacher 125] and Medvile, 1610 [Guillim1 220].
The fishhook is palewise, couped end to chief and barb to dexter, by default. Some Society examples terminate in a ring, but the fact is considered an unblazoned artistic detail. See also hook.
Uilliam Ó Seaghdha bears: Sable, a fishhook Or.
Ragnarr fra Dyflinnarskiri bears: Per chevron sable and Or, three fishhooks counterchanged.
Drosten Sutherland bears: Gules, a fishhook reversed Or within a bordure per pale sable and argent.