2. pertaining to or emanating from focus. focal distance. see focal-film distance. focal length. the distance between the lens and an object from which all rays of light are brought to a focus. focal liver disease. widely disseminated micro-abscesses or abscesses, migration paths of helminth larvae.. pertaining to or emanating from focus. focal distance. see focal-film distance. focal length. the distance between the lens and an object from which all rays of light are brought to a focus. focal liver disease. widely disseminated micro-abscesses or abscesses, migration paths of helminth larvae.
The kilogram or kilogramme (SI unit symbol: kg) is the base unit of mass in the International System of Units (SI) (the Metric system) and is defined as being equal to the mass of the International Prototype of the Kilogram (IPK, also known as Le Grand K or Big K).
Kilogram is the primary unit of mass in the SI system. Kilo is a prefix meaning 1000 and is part of official SI nomenclature. Itâs intended to be applied to SI units such as meters, grams and Hz. It would be perfectly appropriate to apply it to other SI units such as kelvins, seconds and so on, although thatâs less frequent.