to examine, study, or inquire into systematically; search or examine into the particulars of; examine in detail.
to search out and examine the particulars of in an attempt to learn the facts about something hidden, unique, or complex, especially in an attempt to find a motive, cause, or culprit: The police are investigating the murder.
—verb (used without object), in·ves·ti·gat·ed, in·ves·ti·gat·ing.
to make inquiry, examination, or investigation.