An Etymological Dictionary of Astronomy and Astrophysics

The location in a → fluid stream where the
→ cross section of the → stream is at a minimum, and fluid velocity is the highest, such as in the case of a → jet issuing out of a → nozzle.

Etymology (EN): L. vena “channel;” contracta, “contracted,” → contract.

Etymology (PE): Šâre-gozar “fluid passage,” → fluid; → passage, terengidé, → contracted.