coaxial cable (coax) A form of electric cable that consists of a single central conductor surrounded by and insulated from a concentric sheath usually fabricated from an interwoven fine wire mesh. One or more coaxial cables may be included in multicore cable to provide paths for high-frequency or other special signals. The physical dimensions of coax are usually arranged to present a particular characteristic impedance (50 ohms or 75 ohms) to electric signals. See also broadband coaxial systems, Ethernet.

coaxial cable Communications cable consisting of a central conductor with surrounding insulator and tubular shield. They are used to transmit high-frequency signals. Most domestic television aerials use coaxial cables.