The correct spelling of the word "most sanatory" is /məʊst səˈneɪtəri/. Sanatory refers to something related to health or promoting health, making it an appropriate word for describing a hospital or spa. The "-ory" ending is derived from the Latin word "sānāre" meaning "to heal." Meanwhile, the addition of "most" in front of the word emphasizes its importance and suggests that the place being described is exceptionally conducive to good health.