anomalistic

[Cf. F. anomalistique.]

1. Irregular; departing from common or established rules.

2. (Astron.) Pertaining to the anomaly, or angular distance of a planet from its perihelion.

Anomalistic month. See under Month. -- Anomalistic revolution, the period in which a planet or satellite goes through the complete cycles of its changes of anomaly, or from any point in its elliptic orbit to the same again. -- Anomalistic, or Periodical year. See under Year.

adjective

Departing from the normal: aberrant, abnormal, anomalous, atypic, atypical, deviant, divergent, irregular, preternatural, unnatural. See good/bad, usual/unusual.

[Etymology: ‘uneven’ or ‘deviant’] astronomy The term ‘anomaly’ refers to the angular distance of a planet from its perihelion (the point of closest approach to the Sun), i.e. the angle at the Sun between the radial lines to the planet's current position and to its position at perihelion. The adjective ‘anomalistic’ implies being referenced to the moment of perihelion, the anomalistic year being the period between successive perihelions.