pyrostat
rare
noun
1A thermostat, especially one operating at high temperatures; (originally) specifically a device for automatically regulating the draught through a chimney.
2Any of various automatic devices for detecting a fire and triggering an alarm, sprinkler system, etc.
Origin
Mid 19th century; earliest use found in Andrew Ure (1778–1857), chemist.
- what does —— know?
- what do (or would) you say
- what do you know (about that)?
- what do you think this is—bush week?
- what-d'you-call-it (or what's-its-name)
- whate'er
- whatev
- whatever
- whatever next
- whatevs
- what for?
- what fun!
- what gives?
- what goes around comes around
- what if ——?
- what is he (or she etc.) like?
- what is more
- what makes someone tick
- what matter?
- what next
- what next (or whatever next)
- whatnot
- what of it?
- what of ——?
- what planet are you on?