That part of a circle, parallel to the equator, which is described by a celestial object, between its setting and rising.
See nocturnal arc. ...
The Sailor's Word-Book
·noun An instrument formerly used for taking the altitude of the stars, ·etc., at sea. II. Nocturna...
Webster's Dictionary of the English Language
An instrument chiefly used at sea, to take the altitude or depression of some of the stars about the...
·noun An <<Arch>>. II. Arc ·noun A portion of a curved line; as, the arc of a circle or of an <<Ell...
, or arch The segment of a circle or any curved line, by which all angles are measured. ...
·add. ·- The light of an arc lamp. ...
See diurnal arc. ...
That part of a circle, parallel to the equator, which is described by a celestial body from its risi...
The arc which a planet appears to describe when its motion is direct or progressive in the order of ...
The sun's depth below the horizon when the planets and stars begin to appear. ...
Half the arc described by a heavenly body between its rising and setting. ...