microscope UK /ˈmaɪ.kɹəˌskəʊp/US /ˈmaɪ.kɹəˌskoʊp/noun 2verb 1forms 3phrases 1 noun2 •An optical instrument used for observing small objects.That he might ascertain whether any of the cloths of ancient Egypt were made of hemp, M. Dutrochet has examined with the microscope the weavable filaments of this last vegetable. — 1837 •Any instrument for imaging very small objects (such as an electron microscope). verb1 •To examine with a microscope, to put under a microscope (literally or figuratively).It has a strong germicidal action, as can be verified by staining and microscoping the pus, the characteristic micro-organisms disappearing rapidly under its use. — 1897 formsmicroscoped · microscoping · microscopes Phrases with microscope under the microscopeUnder close scrutiny or examination.