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ascesis

[uh-see-sis]
noun, plural as·ce·ses [uh-see-seez] /əˈsi siz/.
  1. askesis.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ascesis

ascesis

noun plural -ses (-siːz)
  1. the exercise of self-discipline

Word Origin for ascesis

C19: from Greek, from askein to exercise
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