VIEWER DISCRETION IS ADVISED... for any member or lurker out there who is stricken with the compulsion to counter the term "currency" as hereinabove used and validated, you will be in for a rude awakening if you consult Google.
My idea of currency is the same as yours: paper money, banknotes, greenbacks sawbucks, scratch, etc. Not so! One gem I encountered is the epitome of circular reasoning using the term currency, to define it:
"Currency refers to a promissory note or a coin that is presented in the form of currency." (emphasis mine.) And further investigation will only cause you to be hopelessly mired in the slippery slope of INR, rupees, paisa, as well as a colorful display of international banknotes, both obsolete and current.
One day you wake up, at age 70, and discover something you thought you knew all along and took for granted is common knowledge, only to find out you were wrong. 🐓