anything considered to be an important or characteristic virtue: Tenacity is his cardinal virtue.
cardinal virtues, Ancient Philosophy. justice, prudence, temperance, and fortitude.
Origin of cardinal virtue
Middle English word dating back to 1300–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for cardinal virtues
the most important moral qualities, traditionally justice, prudence, temperance, and fortitude
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