Bank
Middle English: from Old Norse bakki, of Germanic origin; related to bench. The senses ‘set of things in rows’ and ‘tier of oars’ are from French banc, of the same ultimate origin.
wiktionary
From Middle English banke, from Middle French banque, from Old Italian banca(“counter, moneychanger's bench or table”), from Lombardic bank(“bench, counter”), from Proto-West Germanic *banki, from Proto-Germanic *bankiz(“bench, counter”), from Proto-Indo-European *bʰeg-(“to turn, curve, bend, bow”). Doublet of bench and banc.
From Middle English bank, from Old English hōbanca(“couch”) and Old English banc(“bank, hillock, embankment”), from Proto-Germanic *bankô. Akin to Old Norse bakki(“elevation, hill”), Norwegian bakke(“slope, hill”).
From Middle English bank(“bank”), banke, from Old French banc(“bench”), from Frankish *bank. Akin to Old English benc(“bench”).
Probably from French banc. Of Germanic origin, and akin to English bench.
etymonline
bank (n.1)
"financial institution," late 15c., originally "money-dealer's counter or shop," from either Old Italian banca or via French banque (itself from the Italian word), both meaning "table," from a Germanic source (such as Old High German bank "bench, moneylender's table"), from Proto-Germanic *bankiz- "shelf," *bankon- (see bank (n.2)). The etymonlogical notion is of the moneylender's exchange table.
As "institution for receiving and lending money" from 1620s. In games of chance, "the sum of money held by the proprietor or one who plays against the rest," by 1720. Bank holiday is from 1871, though the tradition is as old as the Bank of England. To cry all the way to the bank was coined 1956 by U.S. pianist Liberace, after a Madison Square Garden concert that was panned by critics but packed with patrons.
bank (n.2)
"natural earthen incline bordering a body of water," c. 1200, from a Scandinavian source such as Old Norse *banki, Old Danish banke "sandbank," from Proto-Germanic *bankon "slope," cognate with *bankiz "shelf" (see bench (n.)). As "rising ground in a sea or rover, shoal," from c. 1600. As "bench for rowers in an ancient galley," 1590s.
There probably was an Old English cognate but it is not attested in surviving documents. The nasalized form likely is a variant of Old Norse bakki "(river) bank, ridge, mound; cloud bank," cognate with Swedish backe, Danish bakke "hill, rising ground."
bank (v.1)
"to act as a banker," 1727, from bank (n.1). As "to deposit in a bank" from 1833. Figurative sense of "to rely on" (i.e. "to put money on") is from 1884, U.S. colloquial. Related: Banked; banking; bankable.
bank (v.2)
1580s, "to form a bank or slope or rise," from bank (n.2). Meaning "to rise in banks" is by 1870. That of "to ascend," as of an incline, is from 1892. In aeronautics, from 1911. Related: Banked; banking.
bank (v.3)
originally in billiards, "to make (the cue ball) touch the cushion (bank) of the table before touching another ball," by 1909, from a specialized sense of bank (n.2); probably abstracted from bank-shot (n.), which is attested by 1889. Related: Banked; banking.
