investigate

UK: /ɪnˈvɛstɪgeɪt/ US: /ɪnˈvɛstɪˌgeɪt/ ,(in ves′ti gāt′)

Inflections of 'investigate' (v): (⇒ conjugate)

investigates

v 3rd person singular

investigating

v pres p

investigated

v past

investigated

v past p

WordReference Random House Learner's Dictionary of American English © 2025

in•ves•ti•gate /ɪnˈvɛstɪˌgeɪt/   v., -gat•ed, -gat•ing. 

1. to look into or examine the particulars of (something) carefully so as to discover something hidden, unique, or complex: [no object]
   The police were called in to investigate.
   [~ + object]
   The scientists were investigating the behavior of dolphins.

in•ves•ti•ga•tor, n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2025

in•ves•ti•gate  (in ves′ti gāt′), v., -gat•ed, -gat•ing. 
v.t. 

1. to examine, study, or inquire into systematically; search or examine into the particulars of;
   examine in detail.
2. to search out and examine the particulars of in an attempt to learn the facts about something hidden, unique, or complex, esp. in an attempt to find a motive, cause, or culprit:
   The police are investigating the murder.

v.i. 

3. to make inquiry, examination, or investigation.

• Latin investīgātus, past participle of investīgāre to follow a trail, search out. See in-², vestige, -ate¹
• 1500–10

in•ves′ti•ga′tive, in•ves•ti•ga•to•ry  (in ves′ti gə tôr′ē, -tōr′ē), adj.  in•ves′ti•ga′tor, n. 

Collins Concise English Dictionary © HarperCollins Publishers::

investigate / ɪnˈvɛstɪˌɡeɪt/ verb

1. to inquire into (a situation or problem, esp a crime or death) thoroughly; examine systematically, esp in order to discover the truth

Etymology: 16th Century: from Latin investīgāre to search after, from in-² + vestīgium track; see vestige

inˈvestigative, inˈvestigatory adjective