Crossword clues for Period of significance. 3 lettersAnswerClueERASignificant period of timeERAHistorically significant periodERASignificant period in historyERASignificant periodERAPeriod of significant activityERASignificant time periodERAPeriod of significance.ERASHistorically significant periodsERASSignificant periods of timeERASSignificant periods of historyERASSignificant periodsEPOCHSignificant periodERASSignificant time periodsDDAYS24-hour periods of significanceERASPeriods of significance.ERASPeriods of historical significanceCHARLESBURNETTKiller of Sheep director, whom Ava DuVernay called "one of the most significant American directors in cinema history of any color, period"COCOBUTTERAInformal term for the period of time when comedian O'Brien had a historically significant bottom?