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summum bonum

[soo m-oo m boh-noo m; English suhm-uh m boh-nuh m]
noun Latin.
  1. the highest or chief good.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for summum bonum

summum bonum

noun
  1. the principle of goodness in which all moral values are included or from which they are derived; highest or supreme good
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