It’s the Oxford English Dictionary ’s word of the day:
Irish English. Expressing sorrow, distress, or regret: “alas!” “woe!” Cf. wirrasthru int. Freq. reduplicated. Chiefly preceded by “Oh”; cf. the etymology. Chiefly in representations of Irish English speech.The word derives from the Irish Mhuire: “in a Mhuire (broadly) /ə wɪrə/ < a , vocative particle +Muire, the name of the Virgin Mary.” My favorite of the OED ’s six citations, from S.J. Weyman’s Wild Geese (1908): “‘Oh, whirra, whirra, what’ll I do?’ the Irishman exclaimed, helplessly wringing his hands.”
Why is wirra my word of the day? Because after lo these many years, I remember it from a Little Rascals short that I saw in childhood (again and again) on television. Oh, wirra, wirra, wirra, someone said. I think it was Alfalfa in drag.