The word for non-communicative communications

I am looking for the word that describes phrases such as "I heard that!" "Been there, done that!" "Totally!" or other such space-fillers. I am drawing a blank.
Thanks.

Interjections. (like "Ouch!" or "Wow!") Or: Nattering. Filling the air with idle chatter. (A phrase a coworker used. Not about me I hope.) Chin-wagging. Babble.

How about: Verbal Styrofoam Peanuts

This may not be the word you're looking for, but a 'rumbelow' is a meaningless word, put in a sea-shanty, to keep the rhythm correct - from Chambers English Dictionary.

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