PIE *wel「回す、回転する」から。語源的にはvoluble「巻き込む」と同じで、バルブを指す。
英語の語源
valve
valve: [14] The etymological notion underlying valve is of a door opening and closing. The word was adapted from Latin valva, which denoted one of the sections of a folding or revolving door, and may have had links with volvere ‘roll’ (source of English revolve). It carried its original meaning with it into English, but it was not used at all widely until various metaphorical senses, such as ‘flap controlling the flow of a fluid’ and ‘half of a shell’, evolved. The electronic valve is so called because current can flow in only one direction through it; the usage dates from the early 20th century.
valve (n.)
late 14c., "one of the halves of a folding door," from Latin valva (plural valvae) "section of a folding or revolving door," literally "that which turns," related to volvere "to roll" (see volvox). Sense extended 1610s to "membranous fold regulating flow of bodily fluids;" 1650s to "mechanical device that works like an anatomical valve;" and 1660s in zoology to "halves of a hinged shell." Related: Valved.
例文
1. The bag is resealed with a simple twist of the valve .
バルブをねじるだけで、エアバッグが再密封されます。
2.The intake valve was jammed open.
吸気バルブが詰まって閉まらない。
3.He replaced a dud valve .
彼は壊れたバルブを交換した。/
4.He also has pro-blems with a heart valve .
彼の心弁にも欠点がある。
5.Exercise is a good safety valve for the tension that builds up at work.