Sill

sill

 or sheet

In geology, a tabular igneous intrusion emplaced parallel to the bedding of the enclosing rock. Although they may have inclined orientations, nearly horizontal sills are most common. Sills may range from a few inches to hundreds of feet thick and up to hundreds of miles long. They include rock compositions of all types.

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sill

1. a shelf at the bottom of a window inside a room

2. a horizontal piece along the outside lower member of a window, that throws water clear of the wall below

3. the lower horizontal member of a window or door frame

4. a continuous horizontal member placed on top of a foundation wall in order to carry a timber framework

5. a flat usually horizontal mass of igneous rock, situated between two layers of older sedimentary rock, that was formed by an intrusion of magma

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sill [sil]

(building construction)

The lowest horizontal member of a framed partition or of a window or door frame.

(civil engineering)

A timber laid across the foot of a trench or a heading under the side truss.

The horizontal overflow line of a dam spillway or other weir structure.

A horizontal member on which a lift gate rests when closed.

A low concrete or masonry dam in a small stream to retard bottom erosion.

(control systems)

A type of robot articulation that has three degrees of freedom.

(geology)

Submarine ridge in relatively shallow water that separates a partly closed basin from another basin or from an adjacent sea.

A tabular igneous intrusion that is oriented parallel to the planar structure of surrounding rock.

(mining engineering)

A piece of wood laid across a drift to constitute a frame to support uprights of timber sets and to carry the track of the tramway.

The floor of a gallery or passage in a mine.

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sill

sill, 1

1. A horizontal timber, at the bottom of the frame of a wood structure, which rests on the foundation.

2. A doorsill.

3. The horizontal bottom member of a window frame or other frame.

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Sill 

a tabular body of intrusive rock that parallels the surrounding layered rock. Sills sometimes reach lengths up to tens of kilometers; those composed of basic and ultrabasic mag-matic rocks are especially common.