April fool
noun
the victim of a practical joke or trick on April Fools' Day.
a practical joke or trick played on that day.
Origin of April fool
First recorded in 1680–90
Example sentences from the Web for april fool
You know, Mrs. Vanderhook expects me to look after the decorations of her April-Fool tea party.
The Gay Gnani of Gingalee |Florence HuntleyBertie walks slowly toward the door, but stops halfway there, and asks, "Is it April-fool's Day?"
British Dictionary definitions for april fool
April fool
noun
an unsuspecting victim of a practical joke or trick traditionally performed on the first of April (April Fools' Day or All Fools' Day)