‘纯属’ is an adverbial phrase meaning 'purely,' 'entirely,' or 'solely.' It emphasizes that something is completely and exclusively of a certain nature, with no mixture or exception. The first character 纯 (chún) means 'pure' or 'unadulterated,' while 属 (shǔ) here functions as a verb meaning 'to belong to' or 'to be classified as' — together, they literally convey 'belongs purely to [X],' implying exclusivity and absoluteness.

This phrase is commonly used in formal or semi-formal speech and writing to downplay intention, deny responsibility, or stress objectivity — for example, when clarifying that an outcome was accidental or that a statement reflects no personal bias. It typically precedes nouns (e.g., 纯属误会 — 'purely a misunderstanding') or verbs (e.g., 纯属虚构 — 'entirely fictional'). It carries a slightly defensive or explanatory tone and is rarely used in casual, colloquial conversation.