Wikipedia

Pico-

Also found in: Dictionary, Medical, Acronyms, Encyclopedia.
This article is about the SI prefix. For other uses, see Pico (disambiguation).

Pico- (unit symbol p-) is a unit prefix in the metric system denoting a factor of 1 trillionth (0.000000000001); that is, 10-12.

Derived from the Spanish word pico, "peak," "beak," "bit," pico- is one of the original twelve prefixes defined in 1960 when the International System of Units was established.[1]

Atomic radii range from 28 picometers (pm) for helium to 260 pm for caesium. One picolight-year (ply) is about nine kilometers (six miles).

SI prefixes
Prefix Base 10 Decimal English word Adoption[nb 1]
Name Symbol Short scale Long scale
yotta- Y- 1024 1000000000000000000000000  septillion  quadrillion 1991
zetta- Z- 1021 1000000000000000000000  sextillion  trilliard 1991
exa- E- 1018 1000000000000000000  quintillion  trillion 1975
peta- P- 1015 1000000000000000  quadrillion  billiard 1975
tera- T- 1012 1000000000000  trillion  billion 1960
giga- G- 109 1000000000  billion  milliard 1960
mega- M- 106 1000000  million 1873
kilo- k- 103 1000  thousand 1795
hecto- h- 102 100  hundred 1795
deca- da- 101 10  ten 1795
100 1  one –
deci- d- 10−1 0.1  tenth 1795
centi- c- 10−2 0.01  hundredth 1795
milli- m- 10−3 0.001  thousandth 1795
micro- μ- 10−6 0.000001  millionth 1873
nano- n- 10−9 0.000000001  billionth  milliardth 1960
pico- p- 10−12 0.000000000001  trillionth  billionth 1960
femto- f- 10−15 0.000000000000001  quadrillionth  billiardth 1964
atto- a- 10−18 0.000000000000000001  quintillionth  trillionth 1964
zepto- z- 10−21 0.000000000000000000001  sextillionth  trilliardth 1991
yocto- y- 10−24 0.000000000000000000000001  septillionth  quadrillionth 1991
  1. ^ Prefixes adopted before 1960 already existed before SI. The introduction of the CGS system was in 1873.

See also

  • RKM code

References

  1. ^ "Resolution 12 of the 11th CGPM". International Bureau of Weights and Measures. 1960. Retrieved 2020-05-14.
This article is copied from an article on Wikipedia® - the free encyclopedia created and edited by its online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of Wikipedia® encyclopedia articles provide accurate and timely information, please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.

Copyright © 2003-2025 Farlex, Inc Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.