Irish goodbye is a slang term with its origins in the Irish-American neighborhoods of New York City and Boston. The term refers to the practice of inconspicuously leaving a place where one has gathered with friends (usually for quite some time) without ever formally announcing that one is leaving. Note that an Irish goodbye requires a conscious decision by the person to leave without bidding adieu. It is a decision that reflects the leaver’s dislike of making himself the center of attention and an austere disdain for showy and perhaps empty formalities. The Irish goodbye also allows a person to disappear from a function with the utmost expediency without spending extra time on “thank-yous” etc.
I never knew there was a term for this type of jerkwad. You spend a few hours with a person or persons, drinking, laughing and carrying on, and suddenly they’re gone and everyone spends time trying to figure out where they went. F that!