cash (n.)youdaoicibaDictYouDict
1590s, "money box;" also "money in hand, coin," from Middle French caisse "money box" (16c.), from Provençal caissa or Italian cassa, from Latin capsa "box" (see case (n.2)); originally the money box, but the secondary sense of the money in it became sole meaning 18c. Cash crop is attested from 1831; cash flow from 1954; the mechanical cash register from 1878.

Like many financial terms in English (bankrupt, etc.), ultimately from Italian. Not related to (but influencing the form of) the colonial British cash "Indian monetary system, Chinese coin, etc.," which is from Tamil kasu, Sanskrit karsha, Sinhalese kasi.
eagle (n.)youdaoicibaDictYouDict
mid-14c., from Old French egle, from Old Provençal aigla, from Latin aquila "black eagle," fem. of aquilus, often explained as "dark colored" (bird); see aquiline. The native term was erne. Golf score sense is by 1908 (according to old golf sources, because it "soars higher" than a birdie). As the name of a U.S. $10 coin minted from 1792 to 1933, established in the 1786 resolution for a new monetary system (but at first only the desperately needed small copper coins were minted). The figurative eagle-eyed is attested from c. 1600.
half-cent (n.)youdaoicibaDictYouDict
U.S. copper coin minted from 1793 to 1857, established and named in the 1786 resolution for a new monetary system; see half + cent.
half-eagle (n.)youdaoicibaDictYouDict
U.S. $5 gold coin minted from 1795 to 1929, authorized in the 1786 resolution for a new monetary system; see half + eagle in the coinage sense.
ruble (n.)youdaoicibaDictYouDict
unit of the Russian monetary system, 1550s, via French rouble, from Russian rubl', perhaps from Old Russian rubiti "to chop, cut, hew," so called because the original metallic currency of Russia (14c.) consisted of silver bars, from which the necessary amount was cut off; from Proto-Slavic *rub-, from PIE root *reub-, *reup- "to snatch" (see rip (v.)).