Fr.: valve, soupape
Any device that halts or regulates the flow of a fluid through a passage, pipe, etc.
From L. valvae "leaves of a door."
Daricé, leterally "small door, window," → stop. Supâp, loan from Fr. soupape, from O.Fr. sourpape, probably from souspape "a blow under chin," from sous "under," from L. subtus, → sub-, + *pape "jaw," from paper, from L. pap(p)are "to eat."
Fr.: mécanisme de valve
A mechanism proposed by Eddington to explain → stellar pulsations. Same as the → kappa mechanism. In this analogy the stellar layer acts like a heat engine with radiation taking the role of stream. The expanding and contracting layer acts as the piston, and the opacity of the layer behaves as the valve mechanism (Eddington, 1917, The pulsation theory of → Cepheid variables, The Observatory 40, 290).