means A wrist-worn computer that tells the time alongside notifications, fitness tracking, and apps, syncing with your phone to keep you tethered to everything at a glance.

from A straightforward compound of "smart" and "watch." The "watch" half is the older piece: a portable timepiece, named from the same root as keeping watch — the night watch, the watchman — because early ones helped mark the hours one stood guard or stayed awake. "Smart" had long meant clever or sharp (originally tied to a sting or pain — a "smart" blow — before it drifted toward intelligence), and it was bolted onto gadgets in the late 20th century to mean computer-enhanced, as in smartphone. The smartwatch followed naturally once phones got smart, with the modern wrist-computer arriving in earnest in the 2010s.