a small metal or rubber ring placed around a hole for a rope or wire to pass through, in order to make the hole stronger （织物或皮革上用以加固扣眼的）金属环，金属圈 - (British English) (North American English tube)
a small tube placed in a child’s ear in order to drain liquid from it when there is an infection 鼓室通气管；中耳引流管
Word Originearly 17th cent. (in nautical use in the sense ‘a circle of rope used as a fastening’): from obsolete French grommette, from gourmer ‘to curb’, of unknown ultimate origin. Current senses date from the mid 20th cent.