Senses
究竟 actually
used in a question to ask for further details or for a final answer; exactly; really
究竟 after all
used to emphasize a fundamental fact or a final conclusion; when all is said and done; in the end
究竟 outcome
the final result or the full facts of a situation; the bottom of a matter; what actually happened
究竟 to investigate thoroughly
to go to the bottom of a matter; to reach a complete understanding; to finish or conclude