a unit of distance, usually used to measure the distance to a star, equal to 206,265 astronomical units (3.0857 x 10 kilometers or 1.92 x 10 miles or 3.2616 light years): it is the distance at which an angle of 0° 0? 1? (one second of arc) would form a triangle having an opposite side with a length of one astronomical unit: abbrev. pc
Origin of parsecpar(allax) + sec(ond)
A unit of astronomical length based on the distance from Earth at which stellar parallax is one second of arc and equal to 3.258 light-years, 3.086 × 1013 kilometers, or 1.918 × 1013 miles.
Origin of parsecpar(allax) + sec(ond)1.
- (astronomy, metrology) parallax second
Contraction of parallax second.