Word Lab
cable · wire
Usage — not pronunciation
The rule
A wire is a single strand of metal — thin, often bare or lightly insulated, used to conduct electricity or for structural jobs like fencing. A cable is a bundle of wires (or fiber-optic strands) twisted or bound together inside a protective outer sheath — thicker and stronger, and the more precise word whenever multiple wires are involved. In everyday speech, people often say "wire" loosely for what's technically a cable — like a phone charger — and it's understood, but "cable" is the accurate term.
Quick tip
If it's a single bare strand, "wire" is correct. If you mean the whole cord with several wires inside a plastic casing — a phone charger, an HDMI cord, a steel support line — "cable" is the precise word, even though "wire" is often used loosely for the same thing in casual speech.
Wire — a single strand
Cable — a bundle of wires in a protective sheath
Everyday overlap — casual "wire" for what's technically a cable
Full breakdown
The words come from very different origins. "Wire" traces back to Old English wīr, which just meant a thin, twisted strand of metal — the sense has barely changed in a thousand years. "Cable," by contrast, comes through Old French/Anglo-Norman from Latin capulum, and originally meant a thick rope — specifically a ship's anchor rope. That nautical sense is why a "cable length" is still a real unit of nautical distance (roughly one-tenth of a nautical mile, based on the length of a ship's anchor cable). The word only picked up its electrical meaning in the 1800s, once telegraph and undersea communication lines started being built the same way ships' ropes were: many individual strands wound together for strength, then wrapped in a protective layer.
That history is basically still the technical definition: a cable is built from wires, not the other way around. A lamp cord, a phone charger, an Ethernet cord, and a suspension bridge's main support line are all "cables" because each one bundles multiple wires (or, for the bridge, many steel strands) inside an outer casing or binding. A single strand on its own — the bare copper inside that cable, a coat-hanger wire, chicken wire, a guitar string — is just a "wire."
Both words also show up in fixed expressions that don't follow the literal rule and can't be swapped: you send a "wire transfer," not a "cable transfer" (a holdover from when international money transfers really did go out over telegraph wire); "wire fraud" is a specific legal term; a "live wire" describes both a dangerous exposed wire and, informally, an energetic person; "down to the wire" (at the very last moment) comes from a wire once stretched across a horse-racing finish line; "get your wires crossed" means to misunderstand each other. "Cable," meanwhile, keeps its own fixed compounds: "cable car," "cable TV"/"cable news," and "cable-knit" (a sweater pattern that looks like twisted rope). None of these idioms follow the technical wire-vs-cable rule — they're just fixed by convention, so they have to be learned as whole phrases rather than reasoned out.
How teachers explain this
Approved tips from the community, sorted by helpfulness
Comments
Comments are reviewed before they appear publicly.