investigatory adj. + Add to list US //ˌɪnˈvɛstəɡəˌtɔɹi// UK //ɪnvˈɛstɪɡətəɹˌi// in·ves·ti·ga·to·ry SynonymsEtymology Synonyms fact findinginvestigativeOrigin From investigate + -ory.