Glossary of Wire & Cable Terminology

m - Abbreviation for meter. See meter.

M - Abbreviation for Mylar^®. See Mylar^®. Mylar^® is a trademark of the DuPont de Nemours Co. Also abbreviated
as MY.

mA - Abbreviation for milliampere, one-thousandth (10^-3) of an ampere.

MAG. OX. - Abbreviation for magnesium oxide.

MAGNET WIRE - Insulated copper wire used for winding coils, motors, and transformers.

MAINS - The source of domestic electrical power distributed nationally throughout the U.K. The mains frequency is the frequency at which the electrical power is supplied. This is 50 hertz in the U.K. and 60 hertz in the U.S.

MARKER TAPE - A tape laid parallel to the conductors under the sheath in a cable, imprinted with the manufacturer’s name and the specification to which the cable is made.

MARKER THREAD - A colored thread laid parallel and adjacent to the strand in an insulated conductor which identifies the manufacturer and sometimes the specification to which the wire is made.

MAT - Abbreviation for material.

MATV - Abbreviation for Master Antenna TV.

MAX - Abbreviation for maximum.

Mbps - Abbreviation for megabits per second.

MC - Abbreviation for megacycle.

MCM - Abbreviation for one thousand (1,000) circular mils, e.g., 500 MCM = 500,000 circular mils.

MECHANICALAL SPLILICE - A fiber splice accomplished by fixtures or materials, rather than by thermal fusion. Index matching material may be applied between the two fiber ends.

MEDIUM FREQUENCY - See frequency band.

MEGA - A prefix to a unit, denoting a multiple of one million (1,000,000) of that unit.

MEGAHERTZ - One million (1,000,000) cycles per second. Abbreviation MHz.

MEGAWATT - One million (1,000,000) watts. Abbreviation MW.

MELAELAELAMINE - A thermosetting resin chemically known as melamine formaldehyde. It has excellent resistance to acids and alkalies and good resistance to water and solvents. Has high strength, high insulation resistance as compared to plastics.

MESA - Abbreviation for Mining Enforcement and Safety Administration. Formerly PBM (Pennsylvania Bureau of Mines).

MESSENGER - The linear supporting member, usually a high strength steel wire, used as the supporting element of a suspended aerial cable. The messenger may be an integral part of the cable or exterior to it.

METER - The unit of length defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second. One meter equals 39.3701 inches. Abbreviation m.

MF - Abbreviation for medium frequency. See frequency band.

Mfd - Abbreviation for microfarad. See microfarad.

MFG. - Abbreviation for manufacture/manufacturing.

MFT - Abbreviation for one thousand (1,000) feet.

MHD - Abbreviation for medium hard drawn copper wire.

Mho - The unit of conductivity. The reciprocal of an ohm.

MHz - Abbreviation for megahertz, one million (1,000,000) cycles per second. Formerly mc. See megahertz.

MI - Nomenclature for mineral insulated cable, made with one or more conductors using mineral for insulation and overall solid metal tube sheath.

MICA - A transparent silicate which separates into layers and has high insulation resistance, high dielectric strength, and high heat resistance.

MICRO - A prefix to a unit, denoting a submultiple of one-millionth (10^-6) of that unit.

MICRO BEBENDING - Minute but sever bends in the fiber of fiber optic cable that result in light displacement and increased loss. Most micro bending can be avoided by the correct selection of materials and proper cabling, handling, and installation techniques.

MICROFARAD - A unit of measure for capacitance. One-millionth (10^-6) of a farad. Abbreviation μF or Mfd.

MICROMETER - A unit of length equal to one-millionth (10^-6) of a meter, formerly called micron. Abbreviated ìm.

MICROMINIM^® - Ultra-flexible micro-miniature wire. A trade name of Standard Wire & Cable Co.

MICRON - A unit of length equal to one-millionth (10^-6) of a meter, now renamed as the micrometer. Abbreviated μm.

MICROSECOND - One-millionth (10^-6 ) of a second .

MICROWAVE - An electromagnetic wave with a wavelength in the range 3 millimeters to 1-3 meters, i.e., between infrared radiation and radio waves on the frequency spectrum. See frequency band.

MICROWAVE FREQUENCY - See frequency band.

MIGRATION - The movement of the non resinous plasticizers in vinyl which takes place at elevated or lowered temperatures. The migrating plasticizer from the jacket will contaminate the polyethylene core of a coaxial cable and thus change its electrical characteristics.

MIKE CABLE or MICROPHONE CABLE - A flexible, generally shielded cable used to connect the microphone to the amplifier.

MIL - a) Abbreviation for one-thousandth (10^-3) of an inch (0.001"). b) A unit used in measuring the diameter of wire or thickness of insulation. c) Abbreviation for military specification (mil spec).

MIL-C - Military cable specification.

MILLI - A prefix to a unit, denoting a submultiple of one-thousandth (10^-3) of that unit.

MILLIMETER - Unit of measure for linear distance. One millimeter equals one-thousandth (10^-3) of a meter. Abbreviation mm.

MILLISECOND - One-thousandth (10^-3) of a second. Abbreviation ms.

MIL SPEC - Abbreviation for military specification.

MIL STD - Abbreviation for military standard.

MIL-W - Military wire specification.

MIN. - Abbreviation for minimum.

MINIATURE WIRE - Refers to insulated conductors of approximately 20 to 34 AWG with a small overall diameter as compared to usual constructions.

MIP - Abbreviation for mylene irradiated polymer.

mm - Abbreviation for millimeter. See millimeter.

MMfd - Abbreviation for one-trillionth (10^-12) of a farad. Commonly referred to as a picofarad (pF).

MODAL DISPERSION - Pulse spreading due to multiple light rays traveling different distances and speeds through a fiber.

MODE - A path of light through a fiber of a fiber optic cable.

MODE FIELD DIAMETER - In single-mode fiber, the region in which light propagates is larger than the glass core diameter. This mode field diameter is a measured value and often listed as a requirement with core diameter in fiber specifications.

MODES - Individual paths in optical waveguides. Single-mode fiber has only one mode, the fundamental mode, while multi-mode fiber has several hundred modes. The upper limit to the number of modes is determined by the core diameter of the waveguide.

MODULUS OF ELASTICITY - The ratio of stress to strain in an elastic material.

MOISTURE RESISTANCE - Ability of a material to resist absorbing moisture from the air or when immersed
in water.

MOLDED PLUG - A connector, male or female, molded on either end of a cord or cable.

MONOMER - The basic chemical unit used in building a polymer.

MP - Abbreviation for multipurpose cable.

MPa - Abbreviation for mega pascal (10⁶ pascals), the metric unit of pressure.

MPG - Abbreviation for multipurpose general purpose cable.

MPP - Abbreviation for multipurpose plenum cable.

MPR - Abbreviation for multipurpose riser cable.

MSHA - Abbreviation for Mining Safety and Health Administration.

MT - Abbreviation for machine tool wire used for internal wiring of appliances or tools. Solid or stranded conductor. Thermoplastic insulations.

MTW - Abbreviation for machine tool wire, plastic insulated, 600 volt, varies 90° C to 105° C.

MULTI-CONDUCTOR - More than one conductor within a single cable complex.

MULTI-MODE FIBEIBEIBER - An optical fiber whose core diameter is large compared with the optical wavelength and thus can contain a large number of modes.

MULTIPLEX - Being or relating to a system of transmitting several messages/signals simultaneously on the same circuit or channel.

MV - Abbreviation for millivolt, one-thousandth (10^-3) of a volt.

MW - a) Abbreviation for megawatt, one million (10⁶) watts. b) Abbreviation for milli watt. One-thousandth (10^-3) of a watt. c) Usually, used in reference to one thousand (1,000) volt plastic insulated wire covered by MIL-W-76.

MY - Abbreviation for Mylar^®. See Mylar^®. Mylar^® is a trademark of the DuPont de Nemours Co. Also abbreviated as M.

MYLAR^® - Trade name for DuPont de Numerous Co. polyester material (polyethylene terephtalate) used in the form of a tape. A synthetic compound with high dielectric properties. Abbreviated as MY and M.