[globular-toast]

Yep, all of the following make perfect sense to me, they're just non-idiomatic:

- Don't put your hand in water that's boiling,

- Add the pasta to water that's boiling,

- That saucepan is full of water that's boiling.

If "boiling water" were a distinct word, all of these sentences would change meaning compare to their idiomatic counterparts.