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thermosiphon

[thur-muh-sahy-fuh n]
noun
  1. an arrangement of siphon tubes that enables water in a heating apparatus to circulate by means of convection.

Origin of thermosiphon

First recorded in 1825–35; thermo- + siphon
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for thermosiphon

thermosiphon

noun
  1. a system in which a coolant is circulated by convection caused by a difference in density between the hot and cold portions of the liquid
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012