contignatio

contignātĭo, ōnis, f. [contigno, a joining together of beams; hence, concrete],

a floor composed of joists and boards; a story, floor , Caes. B. C. 2, 9; 2, 15; Auct. B. Alex. 1; Vitr. 2, 9; Liv. 21, 62, 3; Pall. 1, 9, 2 al.