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thallic

American  
[thal-ik] / ˈθæl ɪk /

adjective

Chemistry.
  1. of or containing thallium, especially in the trivalent state.


thallic British  
/ ˈθælɪk /

adjective

  1. of or containing thallium, esp in the trivalent state

"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 thallic

First recorded in 1865–70; thall(ium) + -ic