'microscopist' originates from the noun 'microscope' (from Greek 'mikros' meaning 'small' and 'skopein' meaning 'to look') combined with the agent-forming suffix '-ist' (from French/Latin meaning 'one who practices or is concerned with').

'microscope' entered English via French and New Latin (from Greek 'mikros' + 'skopein'); the English agent noun 'microscopist' was formed by adding the suffix '-ist' to 'microscope', producing 'microscopist' in modern English.

Initially it meant 'one who uses or looks through a microscope'; over time it has come to denote someone trained or specialized in microscopy and microscopic analysis.