bone (v.) Look up bone at Dictionary.com
especially in bone up "study," 1880s student slang, probably from "Bohn's Classical Library," a popular series in higher education published by German-born English publisher Henry George Bohn (1796-1884) as part of a broad series of "libraries" he issued from 1846, totaling 766 volumes, continued after 1864 by G. Bell & Sons.
bone (n.) Look up bone at Dictionary.com
Old English ban "bone, tusk," from Proto-Germanic *bainam (cognates: Old Frisian ben, Old Norse bein, Danish ben, German Bein). No cognates outside Germanic (the common PIE root is *os-; see osseous); the Norse, Dutch, and German cognates also mean "shank of the leg," and this is the main meaning in Modern German, but English never seems to have had this sense.