noun, masculine/bla.bla/plural: bla-bla
blah, chit-chat, meaningless talk intended to deceive
“Son discours, c’est un blabla prétentieux pour présenter des banalités.” — His speech is a pretentious blah to present banalities.
Synonyms: baratin
Related: blablater
The word is given as onomatopoeic or possibly related to blaguer by le Trésor de la langue française. It appears in the French language in 1945 and could also be a borrowing from earlier English blah.