grommet

(also grummet/ 5grQmIt;`^rQmIt/ n ring-shaped piece of metal or other strong material used to strengthen a hole (eg in a piece of fabric) （用以加固孔眼的）环, 圈（如织物上的金属扣眼）.

gristle, gristly, grit, grits, grittiness, gritty, grizzle, grizzled, grizzly, Gro, groan, groats, grocer, groceries, grocery, grog, groggily, grogginess, groggy, groin, groom, groove, grooved, groovy, grope, gropingly, gross, gross national product, grossly, grossness, grotesque, grotesquely, grotesqueness, grotto, grotty, grouch, grouchy, ground, ground control, ground crew,