also: エープリルフール
noun
April Fools' Day
Refers to April 1 as the day associated with jokes, false announcements, and playful pranks.
今日はエイプリルフールだから、そのニュースを少し疑った。
Because today is April Fools' Day, I was a little suspicious of that news.
エイプリルフールに企業が冗談の発表をすることがある
Companies sometimes make joke announcements on April Fools' Day.
noun
April Fool!; April Fools' joke
Used casually in expressions such as エイプリルフールだよ after revealing that a surprising statement was only a joke.
「実は海外に引っ越すんだ」と言った後で、「エイプリルフールだよ」と笑った。
After saying, 'Actually, I'm moving overseas,' he laughed and said, 'April Fool!'