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Trinity Sunday

noun
  1. the Sunday after Pentecost, observed as a festival in honor of the Trinity.

Origin of Trinity Sunday

late Middle English word dating back to 1400–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for trinity sunday

Trinity Sunday

noun
  1. the Sunday after Whit Sunday
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