A small ring or eyelet, usually made of metal or plastic, used to reinforce a hole in fabric, tarps, or other materials.
Possibly from French gromette, earlier gromme, with obscure ultimate origin; some sources suggest it may relate to an old word for a curb or ring used in horsemanship.
Surfers call young surfers 'grommets' or 'groms'—probably because like the metal ring, they're small, tough, and essential to holding things together in the lineup.
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