- noun the distance at which a star would have a parallax of one second, equal to 3.26 light years, 31 trillion km or 206 000 AU
- Distance at which a star would have a parallax of one second, and equal to 3.26 light years, 31 trillion kilometres or 206,000AU. Parsecs are the standard measure of distances in the universe beyond the solar system, although parallax is rarely used as a means of establishing stellar distance.
- Acronym for parallax-second. A unit of distance utilized in astronomy equal to approximately 3.08572 × 1016 meters, or about 3.261671 light years. Its abbreviation is pc.