這個拼法底下其實是2個不同的字，意思沒有關係， 只是長得一樣。下面分開列出來。跳到 墊圈（華司） · 洗衣機（口語）
washer
noun核心畫面
A small flat ring, squeezed between two things that are being tightened together. Nobody looks at it. Its whole job is to spread the pressure so nothing is crushed, and to fill the last thin gap so that water or air cannot get out. You usually learn it exists only when one wears thin and a tap starts to drip.
可以想成一個扁扁的小圓環，被夾在兩個正要鎖緊的東西中間。平常沒有人會注意它。它的全部工作就兩件：把壓力攤開，不讓表面…更多收起
可以想成一個扁扁的小圓環，被夾在兩個正要鎖緊的東西中間。平常沒有人會注意它。它的全部工作就兩件：把壓力攤開，不讓表面被鎖壞；再把最後那道細縫填住，讓水和空氣漏不出去。多數人是等到它磨薄了、水龍頭開始滴水，才第一次知道有這個東西。A second word, same spelling
washer
noun核心畫面
Picture the ending -er doing its plain job: it points at whoever or whatever does the action. Wash plus -er is simply 'the one that washes'. For a long time that one was a person standing over a tub; then a machine took the work, and the word moved across without changing. So the picture holds both: a hand in the water, and a drum turning in the corner of a kitchen, doing the same job.
可以想成字尾 -er 在做它最單純的工作：指出「做這件事的那一個」。wash 加 -er，就是「會洗的那一個」。以前…更多收起
可以想成字尾 -er 在做它最單純的工作：指出「做這件事的那一個」。wash 加 -er，就是「會洗的那一個」。以前那一個是人，站在木盆前面洗；後來機器接手了這份工作，字就跟著搬過去，形狀完全沒變。所以這個畫面裡兩個都在：水裡的一雙手，和廚房角落轉個不停的滾筒，做的是同一件事。From the word’s history
From Middle English wasshere, equivalent to wash + -er, with cognates in Dutch wasser and German Wäscher. The ending is the ordinary agent ending, which is why the same word can land on a person or on a machine.
依來源記載，這個字來自中古英語 wasshere，等於 wash 加上 -er，荷蘭語 wasser、德語 Wäscher 是同源詞。-er 就是最普通的「做這件事的人／東西」字尾，所以同一個字可以落在人身上，也可以落在機器身上。
Packet Wiktionary entry 'washer' noun, etymology 1 (source_ref kaikki:3f6f69a190036ae4:260802687:31379): "From Middle English wasshere, wassher, equivalent to wash + -er. Cognate with Dutch wasser, German Wäscher."