Ply

The quicker mixer-upper.

Dear Word Detective: Could you please explain the word “ply”? As a noun, I associate it with “two-ply” paper towels, referring (I guess) to the layers of paper. But as a verb it seems to mean “convince” or “bribe,” as in “ply a politician with money.” I also see it used in reference to ships “plying” oceans, people “plying” their trades, etc. If all these “plys” are the same word, I really don’t see the connection. There’s also the “plywood” people put up over their windows when hurricanes approach. Is that also connected to “ply”? — B.T.

I have a theory about plywood and hurricanes. A reasonable person might ask, and many have, why people in places like Florida run out to buy plywood every time a storm looms. What, they ask, happened to last year’s plywood? My theory (and I admit to being a lifelong plywood-hater) is that as soon as the danger passes, they burn the dreadful stuff, because plywood is an abomination, abhorrent and anathema to nature. Incidentally, as for why residents of the northern US buy new snow shovels every winter, it’s because their garages are impassible tangles of junk they bought on eBay.

The reason that “ply” can mean all those various things that you mention (and more) is that English actually has two verbs “to ply,” which developed separately and are considered different words (although if you go back far enough they turn out to share a common ancestor). Curiously, they both seem to have appeared in English at roughly the same time, in the late 14th century.

The basic sense of one sort of “ply” is “to bend or fold,” and it comes from the Old French “plier,” also meaning “to bend,” which was derived from the Latin “plicare,” meaning “to bend, fold, twist or lay.” In English this “ply” initially meant “to bend or fold,” especially fabric or other material, and “to fold over, double or shape.” This use gave us the noun “ply” meaning “layer or strand,” eventually producing both “two-ply” paper towels and “plywood,” which is composed of thin slices of real wood glued together. The “bend” sense of “ply” also gave us the name of “pliers,” a hand tool used to bend and cut wire as well as to grip and turn bolts, etc.

This “ply” was also used, up until the 18th century, in a figurative sense of “bend” to mean “to change someone’s mind” or, intransitively, “to bend to another’s will,” a sense preserved in the adjective “pliable” meaning “easily influenced” (especially, in the case of politicians, with money).

The other “ply” in English is actually simply an aphetic, or shortened, form of the common verb “to apply,” which also dates back to the 14th century and also comes from the Latin “plicare” (to fold or lay) plus the prefix “ap,” giving the sense of “to bring things into contact” or “to apply force to.” The form “ply” initially meant “to wield a tool, etc. forcefully” or, more generally, to “apply” oneself to a task, career, business, etc. (“He that plies to his business finds it, when grown familiar to him, a state of satisfaction.” 1774). In a nautical context “ply” means to move forward, make progress on one’s course, especially a routine route between two points (“Hardy bargemen who ply Father Thames by day and night from Twickenham Ferry to the Nore.” 1897).