Today, Microsoft Word didn't recognise "microsite". Since I'm hot-desking at work and the defaults aren't my own, it automatically changed it to "crosstie".
This, as well as not being helpful, was not a word I'd ever heard of before. So I looked it up.
Oh, it's sort of from "tie across", and is an American word for sleepers (the things that hold railway tracks in place).
It doesn't, as I'd thought, rhyme with "frosty".