from Wiktionary, Creative Commons Attribution/Share-Alike License
- interj. Making the sound of a kiss; the sound used to indicate sending a kiss through the air; Frequently used in email, chat and text messages to indicate sending a kiss to someone.
- n. The hallmark sound of a fretless bass guitar played with a certain technique, where treble frequencies increase gradually after the attack.
Onomatopoeic. From the sound made when kissing, or the sound of a fretless bass. (Wiktionary)