Investigate thoroughly (5)

I believe the answer is:

delve

(Other definitions for delve that I've seen before include "Look closely (into)" , "Dig - investigate" , "Intensively research (into something)" , "Fish around" , "Reach down and search" .)

I've seen this clue in the Sydney Morning Herald and the Newsday.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.