...the principle of metonymy is simply to substitute for the plain name of a thing a name or phrase based on something connected with it.

In the olden time the currency, you know, was a l in gold and silver, joes, half-joes (Johannes), pistoles, moidores, doubloons, pistareens, ninepences (12+¹⁄₂ cents), and fourpence-half-pennies (6+¹⁄₄ cents) or “fippenny-bits.”

John could be dead as far as I know.

It's amazing—what he lacks in finesse he makes up for in sheer willingness to dorkify himself.