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-iasis

American  
  1. a noun suffix occurring in loanwords from Greek.

    psoriasis.


-iasis British  

combining form

  1. (in medicine) indicating a diseased condition Compare -osis

    psoriasis

"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

Usage

What does -iasis mean? The form -iasis is a suffix used to denote the names of disease or other nouns of state or process. It is often used in medical terms, especially in pathology.The form -iasis comes from Greek -íasis, denoting the names of diseases. It is a common misconception that -íasis comes from the verb iâsthai, meaning “to heal,” which is the source of the combining forms -iatry and iatro-. Instead, -iasis is derived from the Greek verb ending -áein (also ân), with the initial -i- used as a connecting vowel, featuring the noun-forming suffix -sis.

Etymology

Origin of -iasis

< Greek, equivalent to -iā- v. formative + -sis -sis