Observatories

Part of speech: noun

Definitions

1. Structures or facilities equipped to observe celestial bodies and phenomena
2. Institutions dedicated to scientific study and monitoring of astronomical events
3. Places where researchers utilize telescopes or other instruments to gather data about the universe

Etymology: The plural of "observatory" is simply the form you use when there is more than one such institution. The base word was borrowed from French "observatoire", which in turn comes from "observer", to watch or observe, combined with the suffix "-atoire", a place-forming ending that marks a building or room set aside for a particular activity. So an observatory is, etymologically, a place for observing. The French formation mirrors Latin "observatorium", but English took the word through French, which is why its spelling and stress still show the French shape. The core idea stayed constant: the building exists so that someone can keep watch on the sky, and the plural simply counts how many such watchtowers and domes a country or city has built.