D defs.my
Entry 1 sense Webster, 1913

Greensand

/(-sănd`)/ · Green·sand · IPA /ˈɡɹinsænd/
01 n. A variety of sandstone, usually imperfectly consolidated, consisting largely of glauconite, a silicate of iron and potash of a green color,…
  1. 1.
    A variety of sandstone, usually imperfectly consolidated, consisting largely of glauconite, a silicate of iron and potash of a green color, mixed with sand and a trace of phosphate of lime.(Geol.)