a trait of cowardice in a person's character.
What Does 💛 Yellow Heart Emoji Mean?The yellow heart emoji can convey love, just like any other heart symbol or emoji, but its yellow color often gets used to show liking and friendship (as opposed to romantic love).
Origin of yellow streak
An Americanism dating back to 1910–15
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for yellow streak
informal a cowardly or weak trait, characteristic, or flaw in a person's nature
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