什么 (shén me) is an interrogative pronoun meaning 'what' in English. It functions as a question word that asks for information about identity, nature, content, or purpose. Though written with two characters — 什 (shén), a rare character used almost exclusively in this compound, and 么 (me), a grammatical particle — the two together form a single lexical unit with no separable meaning; neither character carries its usual sense here (e.g., 么 alone means 'little' in some dialects but not in this context). The pronunciation is always shén me — never shén mó or other variants.

什么 appears in direct questions ('What is this?'), indirect questions ('I don’t know what he wants'), and rhetorical or emphatic expressions ('What nonsense!'). It can also combine with measure words (e.g., 什么东西 'what thing') or function as a placeholder for unknown or unspecified nouns. Unlike English 'what', it does not change form for subject/object position and is never followed by 'is' or 'are' equivalents in Chinese syntax.