研究 (yán jiū) means 'to research' or 'research'—a core academic and professional activity in Chinese. The character 研 (yán) originally meant 'to grind' or 'to polish', suggesting careful refinement of ideas, while 究 (jiū) means 'to investigate thoroughly' or 'to probe to the root'. Together, they convey systematic, in-depth inquiry aimed at discovering truth, solving problems, or advancing knowledge. It is commonly used in formal, intellectual, or scientific contexts—such as university studies, medical investigations, policy analysis, or technological development.

The word functions flexibly: as a verb (e.g., 我们正在研究这个问题 — 'We are researching this issue'), it often follows subjects and may take objects directly; as a noun (e.g., 这项研究很有价值 — 'This research is very valuable'), it frequently appears with measure words like 项 (xiàng) or 个 (gè). It carries neutral-to-formal register and is rarely used in casual daily speech without academic or professional framing.