a casement with a sash hinged at the bottom.
noun, Railroads. 1. a freight car, usually open at the top and containing one or more hoppers so that bulk cargo can be quickly discharged through its bottom.
noun 1. a self-propelled dredge having compartments in which the dredged material can be carried and dumped through hoppers.
noun 1. a window frame having one or more upper sashes hinged at the bottoms and opening inward.
[hop-er-gras, -grahs] /ˈhɒp ərˌgræs, -ˌgrɑs/ noun, Chiefly Southern U.S. 1. (def 1).