- the meaning of the term (or expression) ‘dead-ass’ is likely a result of metaphoric shift. That is, when one is being serious about something, the truth or validity of that thing becomes indisputable, just like death is indisputable - i.e., by using this term you are claiming that the truth is unquestionable. Furthermore, the analogy can also be drawn to the fact that death is the end of life. In effect, when you say dead-ass you can also mean that you are ending the conversation - i.e., there is nothing left to say or question.
dead-ass
adjective; Phrase; analogy; compounding
verification of the truthfulness of an event; seriously
Etymology : this term is a compound formed from: ‘dead’(lifeless) + ‘ass’(used as a postpositive intensive especially with words of derogatory implication).
Source : While my girlfriend was playing a game on her phone with some friends, one of the friends said something like “for real?” and another friend responded with “dead-ass.” (Conversation. November, 2018) https://www.merriam-webster.com/dictionary/dead-ass https://www.merriam-webster.com/dictionary/dead https://www.merriam-webster.com/dictionary/ass
Last modified: 10 December 2018