What is that stuff that janitors throw over puke?

[Diamonds02]

And what does it do?

[Gala Matrix Fire]

When I worked at an amusement park, we threw sawdust over puke. It soaked up the wet bits so that you could then sweep it up with a broom later without getting the broom soaking wet.

[Beware of Doug]

I think the general term for this type of material (dry stuff used to soak up wet stuff) is sorbents. Cat litter is one.

[OneCentStamp]

I have used both the above-mentioned substances (sawdust and cat litter-type clay) to absorb vomit for easier cleaning.