English
geometrician
From geometric + -ian, presumably by analogy with other words in -ician, such as mathematician.
Formed from geometric + -ian
Proto-Indo-European *meh₁- ‘to measure’
…
Ancient Greek μετρέω ‘to measure’
Ancient Greek γεωμέτρης ‘geometer’
Ancient Greek γεωμετρικός ‘of or for geometry, geometrical’
Latin geōmetricus ‘geometer’
English geometric
Today it means
noun A geometer; a mathematician specializing in the study of geometry.
Language periods are conventional ranges, not dates for this word.
Etymograph / geometrician