Meaning of hydrostat

hy•dro•stat

Pronunciation: (hī'dru-stat"), [key]
— n.
  1. an electrical device for detecting the presence of water, as from overflow or leakage.
  2. any of various devices for preventing injury to a steam boiler when its water sinks below a certain level.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.