熟悉 (shú xī) is an adjective-verb compound meaning 'familiar with' or 'well acquainted with' someone, something, or a situation. The character 熟 (shú) means 'cooked' or 'ripe', but figuratively conveys 'thoroughly known through experience'; 悉 (xī) means 'to know fully' or 'to understand completely'. Together, they emphasize deep, firsthand knowledge gained over time—not just surface recognition, but confident understanding and ease of use.

This word is commonly used in daily life to describe familiarity with people (e.g., colleagues), places (e.g., a city), routines (e.g., software or procedures), or concepts (e.g., grammar rules). It often appears after the subject and before the object: 我很熟悉这个软件 (I’m very familiar with this software). While it can function adjectivally (e.g., 他很熟悉), it frequently takes the structure 熟悉 + [noun] and rarely appears with aspect particles like 了 or 过—unlike action verbs, it describes a stable state of knowledge.