Definition of "cryogen" [cryogen]

• A liquid, such as liquid nitrogen, that boils at a temperature below about 110 K (-160°C) and is used to obtain very low temperatures; a refrigerant. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The solid hydrogen, called a cryogen, was expected to last about 10 months -- the mission launched in December 2009."
• "The "cryogen," a new apparatus constructed by Mr.E. Ducretet, from instructions given by Mr. Cailletet, is designed for effecting a fall of temperature of from 70° to 80° C. below zero, through the expansion of liquid carbonic acid."
• "Their idea would require using excess energy from a plant to run a unit producing liquid nitrogen and oxygen - or 'cryogen'."