from
The Collaborative International Dictionary of English v.0.48
grommet \grom"met\ (gr[o^]m"m[e^]t), n. [F. gourmette curb, curb
chain, fr. gourmer to curb, thump, beat; cf. Armor. gromm a
curb, gromma to curb.]
1. A ring formed by twisting on itself a single strand of an
unlaid rope. Sometimes written {grummet}.
[1913 Webster]
2. Any eyelet or ring of metal or other material inserted in
a hole in a sheet of some other material; in sailing, a
metallic ring in or for a sail or a mailbag.
[1913 Webster]
3. A ring of rubber or other insulating material inserted in
a hole in some surface of a device, to prevent wires
passing through the hole from making contact with the
surface; used especially in electrical and electronic
devices, to prevent undesired electrical contact.
[PJC]
4. (Mil.) A ring of rope used as a wad to hold a cannon ball
in place.
[1913 Webster]