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thionic

American  
[thahy-on-ik] / θaɪˈɒn ɪk /

adjective

Chemistry.
  1. of or relating to sulfur.


thionic British  
/ θaɪˈɒnɪk /

adjective

  1. of, relating to, or containing sulphur

"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

Etymology

Origin of thionic

1875–80; < Greek theîon sulfur + -ic