- 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 for 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.