Some uses stay close to the roots. The tech stack nudged its way into other departments; now human resources has its own stack of payroll software and benefits portals. And the bodybuilding usage flowed directly into modern wellness, which has all sorts of non-ripped people obsessing over supplement stacks. Schwarzenegger’s role is now filled by the podcaster and neuroscientist Andrew Huberman — Google his name and “stack,” and you will be surrounded by sites claiming to reveal his preferred cocktail (complete with affiliate links for ordering it yourself).
But all sorts of things can stack. On TikTok, one user revels in her “night stack,” the succession of skin care products she has curated for evening use. People in “decentralized finance” talk a lot about “yield stacking.” People post on X about expanding the skill stacks they offer employers. Jewelry lovers make videos explaining their favorite stacks — maybe a painstakingly selected set of bangles and bracelets, maybe an assortment of necklaces and pendants that cascades down the neck just so.
“Stack” is an abstract, conceptual word; it can denote a pile of whatever you want. But that hasn’t always been the case. English has “stack” because a proto-Indo-European root descended into, among other things, the Old Norse stakkr — which meant, specifically, a haystack. Now Danish has stak, and Norwegian has stakk, and both Swedish and English have stack. We talk about heaps in general and then specify what they’re made of: plumbing, software, peptides. But at some point, people may have been starting with hay and analogizing from there: A stack is a thing that is piled up like hay.
That kind of abstraction is so useful that it has never entirely stopped. A stack was, for a while, a specific unit of measurement: four cubic yards of wood or coal. In the late 1800s it became the word for the dense arrangement of books in libraries. It has been used for chimneys and exhausts and the roof-to-basement plumbing stack of a modern house. Aviation has the stack of planes circling an airport at different altitudes. Guitarists talk about amplifier tone stacks or covet the classic Marshall stack, which has one of the company’s amp heads perched atop two of its speaker cabinets. (Others use “stack” for a hunk of bills totaling $1,000; you might need five or six of them to buy that Marshall rig.) Gaming has multiple uses. One concerns whether or not, say, the double damage boost you just collected will “stack” with the one you already have, quadrupling your total. Another is the reason some people on the user-generated Urban Dictionary define a stack as precisely 64 of something: That’s the maximum number of items that can be piled into a single inventory slot in Minecraft.
Among the finest uses, I think, is the jewelry one, in which a choice arrangement becomes evidence of aesthetic curation and personal style — pieces lovingly collected over time, each one complicating the others to create something more than the sum of the parts. Isn’t this the appeal of the word in every other realm? With a stack, you are never just “taking pills” or “building a résumé” or “putting on moisturizer before bed.” You’re like a mechanic standing over a complex engine, thoughtfully swapping out small parts until the whole thing purrs. All the mundane self-involved preferences you’ve sunk hours into considering — the toner that helped clear your skin; the fuzz pedal that perfectly suited your amp; the L-theanine capsules that paired with magnesium to finally improve your sleep — are now packaged into the kind of singular intellectual creation people could ask you about at parties. Some might argue that the thrill we get from this is only a desperate attempt to find creative satisfaction in a world dominated by the act of selecting of consumer goods, a weak stab at turning shopping into art and science. Others might say that it’s still more fun than just washing your face and passing out.
