Analysis of information sources in references of the Wikipedia article "Sill plate" in English language version.
Groundsill, groundsel: a. sill, ground-plate
Sole Plate: A horizontal 2-by-framing member that is attached directly to the masonry foundation or flooring; also referred to as a sill plate or mudsill
Ground plate: a beam forming the lowest level of a timber frame, onto which the uprights are attached. Also known as a ground sill or sole plate ... Ground sill: see Ground plate.
Groundsill, groundsel: a. sill, ground-plate