[ par-uh-hahy-druh-juhn ]

nounPhysics, Chemistry.
  1. the form of molecular hydrogen in which the nuclei of the two hydrogen atoms contained in the molecule have spins in opposite directions.

Origin of parahydrogen

First recorded in 1925–30; para-1 + hydrogen

Words Nearby parahydrogen Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use parahydrogen in a sentence

  • If they are oriented in opposite directions, it is parahydrogen.

    Unwise Child | Gordon Randall Garrett

British Dictionary definitions for parahydrogen


/ (ˌpærəˈhaɪdrədʒən) /

  1. chem the form of molecular hydrogen (constituting about 25 per cent of the total at normal temperatures) in which the nuclei of the two atoms in each molecule spin in opposite directions: Compare orthohydrogen

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