last strawyoudaoicibaDictYouDict[last straw 词源字典]
"The culminating fact or event in a series of unpleasant or unwelcome ones, causing an extreme reaction not experienced before", Mid 19th cent.; earliest use found in Calcutta Review. With allusion to the proverb it is the last straw that breaks the camel's back.[last straw etymology, last straw origin, 英语词源]