astrometric

The word 'astrometric' is a modern scientific compound built directly from classical Greek elements. The first element, 'astro-', originates from the Greek noun 'astron', meaning 'star', which itself has a deep Indo-European heritage. The second element, '-metric', derives from the Greek adjective 'metrikos', meaning 'pertaining to measurement', which is based on the fundamental noun 'metron' (a measure). When combined, the literal meaning 'star-measuring' precisely describes the field's function: the precise science of measuring the positions and motions of celestial objects, a discipline that evolved from ancient star cataloging into a cornerstone of modern astrophysics and celestial navigation.

Structure: astro (star) + metric (measurement) astro (from Greek 'astron', meaning star); metric (from Greek 'metrikos', relating to measurement, from 'metron', a measure).