What does crossarm mean?
A crossarm is a horizontal bar or crosspiece mounted to an upright structure such as a utility pole, mast, or frame. Its best-known role is on wooden or composite distribution poles, where a crossarm near the top carries insulators and supports the conductors that deliver electricity and telephone service. Typically made of wood, steel, or fiberglass-reinforced polymer, crossarms are built to bear mechanical loads from wire tension, wind, and ice, and they keep energized lines properly spaced and insulated from each other and from the pole itself. The word belongs chiefly to the vocabulary of lineworkers, engineers, and utility crews rather than everyday speech, which gives it a practical, technical flavor. Knowing it is useful for anyone reading utility specifications, discussing storm damage to power lines, or simply wanting to name the familiar bracket that every roadside pole wears on its shoulder.
nounA horizontal bar or crosspiece attached to a post or pole, especially the transverse timber or steel member mounted near the top of a utility pole to carry insulators and support wires.
- A horizontal crosspiece fixed to an upright post or pole, used to support wires, cables, or other attachments (as on utility and telegraph poles).
- Any similar transverse bar serving as a brace or attachment point on a mast, frame, or structure.
"The lineworker replaced a cracked crossarm before securing the new insulators."
"Storm damage had snapped the crossarm clean off the pole, leaving the wires dangling."
"Each insulator sits on the crossarm, keeping the live conductors separated from the grounded pole."
Standard plural; commonly pluralized when describing multiple poles or multiple arms on a single structure.
"The storm toppled several poles and splintered their crossarms."
Every telephone pole you pass is holding up its wires on a crossarm — the quiet workhorse of the power grid that most people have never once named.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of crossarm
The word crossarm is a straightforward English compound of "cross" and "arm," combining two native Germanic elements: "cross," ultimately from Latin crux via Old Norse kross, and "arm," from Old English arm, borrowed in turn from Latin armus, meaning the upper limb of the body. The compound arose in the nineteenth century as telegraph and later electrical infrastructure demanded a name for the transverse member carrying wires on poles. It shares its second element with Latin-derived kin such as armada and armature, and its first with crucifixion-related terms like crucial and crusade.
Related word forms
How crossarm is actually used
Crossarm is a technical term used mainly in the electric utility, telecommunications, and construction trades; it is uncommon in everyday conversation but standard in industry documentation and specifications.
Easily confused with crossarm
A crossbow is a medieval ranged weapon, while a crossarm is a structural crosspiece on a pole or mast.