The word "declinator" refers to an instrument used in astronomy for measuring the angles of declination. However, there are several synonyms for this word that can be used interchangeably in certain contexts. These include "declination circle", "declination instrument" and "declinometer". Each of these terms describes a tool or device that aids in the measurement of declination, which is the angular distance of an object north or south of the celestial equator. Whether you use the word "declinator" or one of its synonyms, the meaning remains the same, and it is a vital tool for astronomers to accurately measure positional information of celestial objects.