Baretti: A dictionary of the English and Italian languages
Suólo, s. m.
1. earth, ground, floor, land, soil, bottom, pavement. Raggualiar —, to level the ground. Uscir dal —, to go mad. — marino, instabile, the surface of the sea. A — a —,one upon the other; 2. the sole of a shoe; 3. the sole of a foot; 4. the hoof; 5. layer, bed.
Florio: a worlde of wordes, or most copious, dictionarie in Italian and English
suolo: a thing that beareth any thing on it, as the earth, the ground, the hand, the bottome, the foundation or superficies of any thing. Also a groundworke, a paucment, a floore, a seeling, a roofe of any roome or place.