kilogram

Etymology

From French kilogramme; synchronically analyzable as kilo- + gram.

noun

1. In the International System of Units, the base unit of mass; conceived of as the mass of one litre of water, but now defined by taking the fixed numerical value of the Planck constant h to be 6.626 070 15 × 10⁻³⁴ when expressed in units of kg⋅m²⋅s⁻¹. Symbol: kg
2. (proscribed) The unit of weight such that a one-kilogram mass is also a one-kilogram weight.