Depends on where you’re from, round here we call them rocks, next county over they call them pebbles, I’ve even heard the term “gravel” but I think that ones French.
Lol it does look like fossilized coral but I'm surprised the pebble people didn't also say levurite. Which can have many spelling. Meaning leave it right where you found it! In all seriousness if it reminds you of a wasp nest in rock form its coral.