'thuja' originates from New Latin, specifically the word 'Thuja', where Greek 'thuia' referred to a fragrant or resinous tree (used in offerings or as incense).

'thuja' changed from the Greek word 'thuia' into New Latin botanical usage as 'Thuja' and was later adopted into English as 'thuja' in the 18th century taxonomic literature.

Initially, it meant 'a fragrant tree used in sacrifices or for incense', but over time it evolved into its current meaning of 'a genus of evergreen coniferous trees (arborvitae)'.