SCORE, n. 1. A notch or incision; hence, the number twenty. Our ancestors, before the knowledge of writing, numbered and kept accounts of numbers by cutting notches on a stick or tally, and making one notch the representative of twenty. A simple mark answered the same purpose. (American Dictionary of the English Language, Noah Webster 1828)
SCORE. n.s. [skora, Islandick, a mark, cut, or notch.] 1. A notch or long incision. 8. Twenty. I suppose, because twenty, being a round number, was distinguished on tallies by a long score. (A Dictionary of the English Language, Samuel Johnson 1st 1755, 4th 1773)
Revelation 13:16 He causes all... ...to be given marks (from Greek charagma) on their right hands, or on their foreheads;
charagma - stamp, mark. From the same as charax; a scratch or etching, i.e. Stamp (as a badge of servitude), or scupltured figure (statue) -- graven, mark.
Revelation 13:17, Revelation 14:9, Revelation 14:11, Revelation 16:2, Revelation 19:20, Revelation 20:4