side-board Copy link Outline 1. ăbăcus (usu. an ornamental s., with a top made of marble or silver)2. perh. mensa (any table, board, etc.) • side-board: 1. ăbăcus (usu. an ornamental s., with a top made of marble or silver): s.s furnished out with embossed silver and gold plate, a. argento auroque caelato ornati, Cic. Tusc. 5, 21, 61: Cato. (For abacus, Hor. uses lapis albus, S. 1, 6, 116.) 2. perh. mensa (any table, board, etc.): v. Lat. Dict. s. v.