- Mount, a mountain in E central California, in the Sierra Nevada Mountains. 14,153 feet (4314 meters).
- a shelf at the bottom of a window inside a room
- a horizontal piece along the outside lower member of a window, that throws water clear of the wall below
- the lower horizontal member of a window or door frame
- a continuous horizontal member placed on top of a foundation wall in order to carry a timber framework
- a flat usually horizontal mass of igneous rock, situated between two layers of older sedimentary rock, that was formed by an intrusion of magma
Word Origin and History for mount-sill
Old English syll "beam, threshold, large timber serving as a foundation of a wall," from Proto-Germanic *suljo (cf. Old Norse svill, Swedish syll, Danish syld "framework of a building," Middle Low German sull, Old High German swelli, German Schwelle "sill"), perhaps from PIE root *swel- (3) "post, board" (cf. Greek selma "beam"). Meaning "lower horizontal part of a window opening" is recorded from early 15c.
- A sheet of igneous rock intruded between layers of older rock. See illustration at batholith.