'archostenosis' originates from New Latin/modern medical coinage, combining the Latin element 'arcus' (via the combining form 'arch(o)-') meaning 'bow' or 'arch' and the Greek word 'stenōsis' (στἐνωσις) from 'stenos' meaning 'narrow'.

'archostenosis' is a modern compound formed in medical Latin/English by joining the Latin-rooted prefix meaning 'arch' with the Greek-derived medical noun 'stenosis'; it did not pass through a distinct medieval English form but entered technical usage in recent centuries as a specialist medical term.

Initially, the component roots separately meant 'arch' (arcus) and 'narrow' (stenos); combined as 'archostenosis' the meaning is straightforwardly 'narrowing of an arch,' a sense retained in modern medical usage.