The word 并不 (bìng bù) is formed by combining the adverb 并, which originally carries meanings of "combining" or "simultaneously," with the fundamental negation word 不 ("not"). In modern usage, however, 并 does not retain its literal meaning here; instead, it functions as an intensifier or emphasizer when paired with 不 (or other negative words like 没). This combination creates a strengthened form of negation that is often used to contradict a prior assumption or expectation, translating to concepts like "actually not," "definitely not," or "by no means." Thus, the formation is grammatical rather than purely lexical, where 并 adds a tone of forceful refutation or clarification to the simple denial expressed by 不.