Where does the word “quid” come from, as in the slang for the British Pound? My dictionary tells me nothing . . . “Unknown origin” is the curse of the inquisitive brain!
It seems weird as well that it doesn’t change from plural to singular . . . it’s correct to say “a quid” as well as “thirty quid”.
There are five designs of pound coin in circulation at the moment.
One design has the royal coat of arms on the reverse and the words DECUS ET TUTAMEN (“An Ornament and a Safeguard” in Latin) around the edge; another has an English emblem and DECUS ET TUTAMEN; another has a Northern Ireland emblem and DECUS ET TUTAMEN; another has a Scottish emblem and the words NEMO ME IMPUNE LACESSIT (“No One Provokes Me with Impunity”); and the fifth has a Welsh emblem and PLEIDOL WYF I’M GWLAD (“True Am I to My Country” in Welsh around the edge).
They all have the queen’s face and some more Latin I won’t bore you with on the obverse.