穷尽 (qióng jìn) is a formal, literary verb meaning 'to exhaust' or 'to fully explore, investigate, or utilize something to its utmost limit.' The character 穷 (qióng) originally means 'poor' or 'destitute,' but in compounds it often conveys the sense of 'reaching the end' or 'leaving no part unexamined'; 尽 (jìn) means 'to exhaust' or 'to use up completely.' Together, they emphasize thoroughness and completeness — not just physical depletion, but comprehensive intellectual, emotional, or practical engagement with a subject, resource, or possibility.

This word is commonly used in academic, technical, or reflective contexts — for example, when describing exhaustive research, complete analysis of data, or relentless pursuit of truth. It carries a tone of rigor and seriousness, rarely appearing in casual speech. While it can describe using up tangible things (e.g., resources), it more frequently applies to abstract domains like knowledge, options, or effort. Its compound structure makes it highly predictable: it always functions as a transitive verb and typically follows subjects expressing agency (e.g., researchers, analysts, or individuals committed to depth).