answers: millionth
context: and milligauss). Metric prefixes may also be used with non-metric units. The choice of prefixes with a given unit is usually dictated by convenience of use. Unit prefixes for amounts that are much larger or smaller than those actually encountered are seldom used. In use, the kilogram, gram, milligram, microgram, and smaller are fairly common. However, megagram (and gigagram, teragram, etc.) are rarely used; tonnes (and kilotonnes, megatonnes, etc. – although these units generally are not used as a measure of mass "per se", but rather TNT energy equivalent of a mass) or scientific notation are used instead. Megagram is </s> others don't), and in physical sciences academia, "μg" remains the sole official abbreviation. In medical data exchange according to the Health Level 7 (HL7) standard, the μ can be replaced by u as well. Micro- Micro- (Greek letter μ or legacy micro symbol µ) is a unit prefix in the metric system denoting a factor of 10 (one millionth). Confirmed in 1960, the prefix comes from the Greek (""), meaning "small". The symbol for the prefix comes from the Greek letter μ (mu). It is the only SI prefix which uses a character not from the Latin alphabet. "mc" is </s> Microlife A microlife is a unit of risk representing half an hour change of life expectancy. Introduced by David Spiegelhalter and Alejandro Leiva, microlives are intended as a simple way of communicating the impact of a lifestyle or environmental risk factor, based on the associated daily proportional effect on expected length of life. Similar to the micromort (one in a million probability of death) the microlife is intended for "rough but fair comparisons between the sizes of chronic risks". This is to avoid the biasing effects of describing risks in relative hazard ratios, converting them into somewhat tangible units. Similarly
question: in the metric system the prefix micro - denotes