My giddy aunt

This exclamation of surprise derives from the archaic meaning of giddy as mad and is first recorded from the late 19th century, although aunts have been described as ‘giddy’ since the early 19th century but not in the form of an exclamation. Quite why the word ‘giddy’ has been applied to ‘aunt’ is not known for sure. Some suggest that the revival of the archaic meaning was due to the popular farce Charley’s Aunt written by Brandon Thomas and first performed in 1892. The farce did portray Charley’s aunt as the archetypal giddy or dotty aunt but the words my giddy aunt do not appear in the farce. The antics of Charley’s aunt could be described as giddy but it is not known who revived the old archaic meaning or why. See also My aunt, My sainted aunt, and Act the giddy goat.