Chinese Abacus. The abacus is first known in China from the Northern Song dynasty through the work of Shao Yong (1011-1077). Like many early inventions it is not clear precisely where it originally came from. Some say Central Asia; some Asia Minor and others China.
Snag(noun) a stump or base of a branch that has been lopped off; a short branch, or a sharp or rough branch; a knot; a protuberance. Snag(noun) a tooth projecting beyond the rest; contemptuously, a broken or decayed tooth.
Definition of snag for Students. 1  1 : a rough or broken part sticking out from something. 2  2 : an unexpected difficulty Our plan hit a snag. 3  3 : a stump or stub of a tree branch especially when hidden under water.