细析 is a formal noun meaning 'detailed analysis' — the character 细 (xì) means 'fine', 'detailed', or 'meticulous', while 析 (xī) means 'to analyze', 'to examine', or 'to separate into components'. Together, they convey the idea of breaking something down carefully and thoroughly to understand its structure, causes, or mechanisms. This term is commonly used in academic, scientific, medical, and technical writing, especially when describing rigorous examination of data, symptoms, experimental results, or complex systems.

Unlike more general terms like 分析 (fēn xī, 'analysis'), 细析 emphasizes depth, precision, and systematic scrutiny. It rarely appears in casual speech and is typically found in reports, research papers, clinical evaluations, or policy reviews. Because it's a compound noun formed from two monosyllabic morphemes, it functions as a single lexical unit and does not take aspect markers or aspect particles like 了 or 过 — it’s usually preceded by verbs such as 进行 (jìnxíng), 做 (zuò), or 开展 (kāizhǎn) to indicate the action of carrying out the analysis.