Sill — definition

1. sill (Noun)

2 definitions

sill (Noun) — Structural member consisting of a continuous horizontal timber forming the lowest member of a framework or supporting structure.

sill (Noun) — (geology) a flat (usually horizontal) mass of igneous rock between two layers of older sedimentary rock.

3 types of
rock stone structural member
4 types
doorsill doorstep threshold windowsill