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thi-

1 American  
  1. variant of thio- before a vowel.

    thiazine.


THI 2 American  
Or T.H.I.

abbreviation

Meteorology.
  1. temperature-humidity index.


THI 1 British  

abbreviation

  1. temperature-humidity index

"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

thi- 2 British  

combining form

  1. a variant of thio-

"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