from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. That point of the orbit of a celestial body which is closest to the star around which the body is orbiting.
from the GNU version of the Collaborative International Dictionary of English
- n. That point, in the real or apparent orbit of one star revolving around another, at which the former is nearest to the latter.
from The Century Dictionary and Cyclopedia
- n. In the orbit of any heavenly body which moves around another, the point where the former approaches nearest to the primary: usually applied to double stars, but also generally to any satellite.
From Ancient Greek περί "around" + ἄστρον "star". (Wiktionary)