is a specific kind of: definite quantity.

is a broader term that covers: measuring block, measuring unit | denier | diopter, dioptre | carat, karat, kt | absorption unit | acceleration unit | angular unit | area unit, square measure | capacity measure, capacity unit, cubage unit, cubature unit, cubic content unit, cubic measure, displacement unit, volume unit | computer memory unit | electromagnetic unit, emu | explosive unit | force unit | linear measure, linear unit | metric, metric unit | miles per gallon | monetary unit | megaflop, MFLOP, million floating point operations per second | teraflop, trillion floating point operations per second | million instructions per second, MIPS | pain unit | pressure unit | printing unit | sound unit | telephone unit | temperature unit | weight, weight unit | mass unit | unit of viscosity | energy unit, heat unit, work unit | langley | Brinell number | point | bit | electrostatic unit ... show more.

derivation: unitise, unitize | unitise, unitize.