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Alphonse and Gaston

or Al·phonse-and-Gas·ton

adjective
  1. marked by a ritualistic courtliness in which two often competing participants graciously but stubbornly defer to each other: a kind of Alphonse and Gaston act in which each man insisted the other go through the doorway first.

Origin of Alphonse and Gaston

after the title characters of a cartoon strip by American cartoonist Frederick Burr Opper (1857–1937), which first appeared in 1905
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018