nanogram

n. very small unit of measure, a billionth of a gram

The kilogram or kilogramme (symbol: kg) is the SI base unit of mass. The kilogram is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal to the mass of one liter of water. It is the only SI base unit with an SI prefix as part of its name. It is also the only SI unit that is still defined in relation to an artifact rather than to a fundamental physical property that can be reproduced in different laboratories.
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Noun
1. one billionth (1/1,000,000,000) gram
(synonym) ng
(hypernym) metric weight unit, weight unit
(part-holonym) microgram, mcg

A measure of weight. One nanogram weighs a billion times less than one gram, and almost a trillion-times less than a pound.

NANOGRAMMA