Petah comes from the internet's phonetic spelling of Peter Griffin from Family Guy, whose distinctive laugh has been clipped and reshared as a standalone reaction for years. Short laugh clips circulated on soundboards and in meme edits alongside sounds like the baby laughing meme, turning a simple giggle into shorthand for finding something absurdly funny. The stretched spelling in Petahhhehehehe captures how the laugh drags on, and that exaggeration helped it spread in short-form videos, gaming edits and comment-style reaction posts.