Muak is the Spanish spelling of the kiss onomatopoeia, and beso simply means kiss, which is why Spanish-speaking creators search for this clip with those exact words. The sound itself is a generic lip-smacking effect rather than a line from a film, show or song, and similar kiss noises circulate widely across meme pages, messaging apps and short-form video. Its staying power comes from that simplicity: a single smack instantly signals affection without needing dialogue, subtitles or context.