Cash
Cash usually refers to money in the form of liquid currency, such as banknotes or coins.
Sometimes used as a street name or slang for Fentanyl.

# Etymology
The English word cash is of the French caisse, itself a borrowing of the Provencal caissa.  That Provencal word is a derivative of the Latin capsa (box, chest), most likely by way of an unattested Vulgar Latin form *capsea; Spanish caja and Portuguese caixa are their respective languages' reflexes.
From the original sense of a box or a chest, the word came to refer to a sum of money such as was or might be contained in one, and eventually to specie or, with the elimination of metallic standards, banknotes. In this sense, it is used in contrast to credit or other financial instruments.
The word "cash" can also be traced back to: Sanskrit karsa, a weight of gold or silver but akin to Old Persian karsha-, a weight. a unit of value equivalent to one cash coin.

# Historical usage in Asia
The word was formerly used also to refer to certain low-value coins used in South and East Asia.  This sense derives from the Tamil kasu, a South Indian monetary unit.  The early European representations of this Tamil word, including Portuguese caxa and English cass, merged the existing words caixa and cash, which had similar connections with money.  In the pre-1818 South Indian monetary system, the cash was the basic coin, with 80 cash equalling a fanam and 42 fanams equalling a star pagoda worth roughly 7s. 8d.
This assimilated Tamil word was then applied to various other coins with which European traders came into contact, including the famous holed cash coins of China, the Chinese cash.  Also called wen, these coins were commonly strung on cords for use in larger transactions; 1000 equalled a tael.
In bookkeeping and finance, cash refers to a current asset account, as opposed to long term assets such as property plant and equipment.
Cash is commonly defined as money in the form of bills or coin, legal tender.
-  Jump up to: 1.0 1.1 "Cash, n.1". OED Online..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
-  Bloch, Oscar, and Walther von Warthburg (Dirs.) (2002). "Caisse". Dictionnaire etymologique de la langue francaise (1er edition Quadrige ed.). Paris: Presses universitaires de France.CS1 maint: Multiple names: authors list (link)
-  Jump up to: 3.0 3.1 "Cash, n.2". OED Online.