(anatomy) One of two openings transmitting nerves and blood vessels to or from the orbit, situated inferiorly between the greater wing of the sphenoid bone and the maxilla.

(informal, often humorous) The referent of it is dangerous or undesirable and should be eliminated.

(astrodynamics) A nearly polar orbit in which a satellite passes over the surface of a planet maintaining the same local mean solar time.

plural of orbital quantum number

(astrodynamics) A halo orbit with nearly straight sides between passes near the orbited body.