What is the equivalent for "dilute" to make more runny?

If I'm dealing with a salt or sugar solution, adding more water to it is called dilution. The same could be said of adding water to a liquid such as milk.

What word would I use if I was dealing with a paste of mud or corn starch? Adding water makes it more runny, less pasty, and dilution seems to be the wrong term to apply in this case.


to thin

As in the idiom:

thin something down TFD idiom

to dilute a fluid.

And:

cut TFD

  1. tv. to dilute something.