'bacterioscopy' originates from combining forms used in modern medical English, specifically the element 'bacterio-' from Greek 'bakterion' meaning 'little rod' (used for 'bacterium') and the suffix '-scopy' from Greek 'skopein' meaning 'to look' or 'to examine'.

'bakterion' (Greek) gave rise to Neo-Latin 'bacterium' and the combining form 'bacterio-'; combined with the Greek-derived suffix '-scopy' (from 'skopein'), the compound 'bacterioscopy' emerged in medical usage in the 19th century to denote microscopic examination of bacteria.

Initially the elements referred specifically to 'looking at rod-shaped organisms' (bacteria as 'little rods'), and over time the compound came to mean the general microscopic examination or inspection of bacteria.