名詞 annulus:

1. a toroidal shape
   同義詞：ring, halo, anulus, doughnut, anchor ring
2. (Fungi) remnant of the partial veil that in mature mushrooms surrounds the lower part of the stem

an.nu.lus

n.（名詞）
【復(fù)數(shù)】 an.nu.lus.es 或 an.nu.li [-lo.]
A ringlike figure, part, structure, or marking, such as a growth ring on the scale of a fish.
環(huán)狀物：環(huán)狀物、部分、結(jié)構(gòu)或標(biāo)志，如魚(yú)鱗上的生長(zhǎng)環(huán)

A ring or group of thick-walled cells around the sporangia of many ferns that functions in spore release.
環(huán)帶：蕨類植物孢子囊周圍具有釋放孢子功能的環(huán)或一組細(xì)胞壁很厚的細(xì)胞
The ringlike remains of a broken partial veil, found around the stipes of certain mushrooms.
菌環(huán)：破損菌幕的環(huán)狀殘留部分，在某些洋菇菌柄周圍可見(jiàn)
Mathematics The figure bounded by and containing the area between two concentric circles.
【數(shù)學(xué)】 圓環(huán)域：以兩個(gè)同心圓為界的圖形或兩圓之間包括的圖形

來(lái)源：
Latin 3nulus [ring] [diminutive of] 3nus
拉丁語(yǔ) 3nulus [環(huán)，環(huán)形物] [] 3nus的小后綴