Investigate

Webster's Practical Dictionary- A Practical Dictionary of the Englih Language · 1884 · p. 219

in-ves'tt-gat, v. t. To follow up, pursue, search into. — Inves'tig a'tion, n. Act of investigating; research; study; inquiry. — Inves'tig a'tor, -ter, n. One who searches diligentty into a subject.