You know it as a shorter, simpler way to say “rhinoceros.” But in the 17th and 18th centuries rhino was slang for “money,” and the related adjective rhinocerical was slang for “wealthy.” And no one is sure why.
These are not the rhinos you’re looking for. (But they sure are cool in Black Panther.)
Rhinoceros, from Greek roots meaning “nose-horned,” entered English around 1300; it referred to the herbivorous odd-toed ungulate, two species of which are found in Africa and three in Southern Asia. Rhino- also appears in combination forms such as rhinoplasty (plastic surgery of the nose; first appearance in print: 1828); rhinolaryngitis (1891); and rhinovirus (1961). As the shortened form of the animal name, the word first appeared in print in 1870. But nearly two centuries earlier it was popularly used in England to mean “cash,” and by 1697 the idiom “ready rhino” (or “ready rino”) was in circulation.
Rhino Entertainment, founded in 1978 as Rhino Records and still going. This single by The Monkees was released in 1983. If there’s a story behind the name, I haven’t found it.
Rhinocerical began appearing in print in 1688, simultaneously with rhino.
Rhinocerical, from Green’s Dictionary of Slang. GDoS gives rhino-fat as a U.S. synonym dating from 1859.
Why rhino? The OED says it may be an “allusion to the value of rhinoceros horn, although this could equally reflect after-the-fact rationalization of a word of different origin, or even punning.” GDoS says “etymology unknown,” but speculates that the word might be a clipping of “sovereign.”
Could there be a connection between rhino and the idiom “paying through the nose”? Language scholar Anatoly Liberman tackled the question in a 2010 post in the Oxford University Press blog; he tracked the idiom back to the late 1600s – the age of rhino – but was unable to establish an etymology. He was able to find “four or five” unsourced origin stories, none of them credible. His verdict on the rhino-pay-through-nose hypothesis:
Clever, but rather improbable, though, as noted, the origin of the idiom in thieves’ cant (or among university wits, who played with Greek words?) cannot be excluded.
Big Rhino folding stool from Kikkerland. In brand names, “rhino” connotes strength.
Bonus link: An alphabetical list of contemporary slang terms for money, including ass-dough, moolah, and skrilla, but not including kale or dinero.