ピロピロMeanings1nounparty horn; party bloweronomatopoeic or mimetic word›Onomatopoeic word for the sound of a party horn or blowout, often used by children or in casual contexts. Also refers to the toy itself.See also: 吹き戻し誕たん生じょう日びパーティーでピロピロを吹ふいた。I blew a party horn at the birthday party.