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definitions

axion

[ak-see-on]

noun Physics.

a hypothetical particle having no charge, zero spin, and small mass: postulated in some forms of quantum chromodynamics.

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Origin of axion

1978; perhaps axi(al current) + -on1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for axion

axion

noun

physics a hypothetical neutral elementary particle postulated to account for certain conservation laws in the strong interaction

Word Origin for axion

C20: from axi (om) + -on
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
Word Origin and History for axion
n.

1978, from axial + scientific suffix -on.

Online Etymology Dictionary, © 2010 Douglas Harper