Joe O’Malley (Irish coffee)

“Joe O’Malley” is sometimes given as the lunch counter slang for “Irish coffee.” However, Irish coffee became popular in the late 1940s and 1950s—at the tail end of the era of lunch counter slang. The reason for the name “Joe O’Malley” is not known.
 
“A ‘Joe O’Malley’ was Irish coffee” was printed in the Sarasota (FL) Herald-Tribune on January 12, 2011. Older, historical citations have not been found.
 
     
Diner Lingo
Q:What does “Joe O’Malley” mean?
A: If you hear a waitress say “Joe O’Malley” at a diner or restaurant, it’s just another way to say “Irish coffee.”
     
Sarasota (FL) Herald-Tribune
Diner language
By Linda Brandt
Posted Jan 12, 2011 at 12:01 AM
(...)
A “Joe O’Malley” was Irish coffee and “50/50 Joe” was coffee with half-and-half.
 
Google Books
Terms of Employment:
The secret lingo of the workplace
By Charlie Croker
London, UK: Random House Books
2012
Pg. 245:
... cowboy coffee (made with chicory), Frosty Joe (iced) and Joe O’Malley (Irish coffee).
 
Twitter
Bluebonnet Diner
@bluebonnetdiner
Diner logo time: Irish Turkey = Corned Beef and Cabbage
Joe O’Malley = Irish Coffee
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