parsec
[ pahr-sek ]
/ ˈpɑrˌsɛk /
noun Astronomy.
a unit of distance equal to that required to cause a heliocentric parallax of one second of an arc, equivalent to 206,265 times the distance from the earth to the sun, or 3.26 light-years.
Origin of parsec
First recorded in 1910–15;
par(allax) +
sec(ond)2
Words nearby parsec
pars intermedia,
pars plana,
pars tympanica,
pars-planitis,
parse,
parsec,
parsee,
parseeism,
parser,
parsha,
parsifal
British Dictionary definitions for parsec
parsec
/ (ˈpɑːˌsɛk) /
noun
a unit of astronomical distance equal to the distance from earth at which stellar parallax would be 1 second of arc; equivalent to 3.0857 × 10 16 m or 3.262 light years
Word Origin for parsec
C20: from
parallax +
second ²
Scientific definitions for parsec
parsec
[ pär′sĕk′ ]
A unit of astronomical length equal to 3.26 light-years. It is based on the distance from Earth at which a star would have a parallax of one second of arc. Its metric equivalent is about 30.8 trillion km (19.1 trillion mi). It is used in measuring distances in interstellar and intergalactic space. The closest star to Earth, Alpha Centauri, is about 1.3 parsecs away. Compare astronomical unit light-year.