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.

Definitions of bank
bank (n.)
sloping land (especially the slope beside a body of water);
they pulled the canoe up on the bank
he sat on the bank of the river and watched the currents
bank (n.)
a financial institution that accepts deposits and channels the money into lending activities;
that bank holds the mortgage on my home
he cashed a check at the bank
Synonyms: depository financial institution / banking concern / banking company
bank (n.)
a long ridge or pile;
a huge bank of earth
bank (n.)
an arrangement of similar objects in a row or in tiers;
he operated a bank of switches
bank (n.)
a supply or stock held in reserve for future use (especially in emergencies);
bank (n.)
the funds held by a gambling house or the dealer in some gambling games;
he tried to break the bank at Monte Carlo
bank (n.)
a slope in the turn of a road or track; the outside is higher than the inside in order to reduce the effects of centrifugal force;
Synonyms: cant / camber
bank (n.)
a container (usually with a slot in the top) for keeping money at home;
the coin bank was empty
Synonyms: savings bank / coin bank / money box
bank (n.)
a building in which the business of banking transacted;
the bank is on the corner of Nassau and Witherspoon
Synonyms: bank building
bank (n.)
a flight maneuver; aircraft tips laterally about its longitudinal axis (especially in turning);
the plane went into a steep bank
bank (v.)
tip laterally;
the pilot had to bank the aircraft
bank (v.)
enclose with a bank;
bank roads
bank (v.)
do business with a bank or keep an account at a bank;
Where do you bank in this town?
bank (v.)
act as the banker in a game or in gambling;
bank (v.)
be in the banking business;
bank (v.)
put into a bank account;
Synonyms: deposit
bank (v.)
cover with ashes so to control the rate of burning;
bank a fire
bank (v.)
have faith or confidence in;
Synonyms: count / bet / depend / swear / rely / look / calculate / reckon