April Fools' Day

April Fools' Day or All Fools' Day, named from the custom of playing practical jokes or sending friends on fools' errands, on April 1. Its timing seems related to the vernal equinox, when nature fools mankind with sudden changes from showers to sunshine. It is a season when all people, even the most dignified, are given an excuse to play the fool. In April comes the cuckoo, emblem of simpletons; hence in Scotland the victim is called "cuckoo" or "gowk", as in the verse: On the first day of Aprile, Hunt the gowk another mile. Hunting the. gowk was a fruitless errand; so was hunting for hen's teeth, for a square circle or for stirrup oil, the lastnamed proving to be several strokes from a leather strap.

(Encyclopaedia Britannica)