不明
ふめい · fumei · JLPT N1 · na-adj
unknown
不明 = not + bright: a light that is not on, so you cannot tell what is there
明 means bright or clear, as in 明天 (tomorrow, the bright day ahead). 不 negates it, so 不明 means not clear, so unknown or ambiguous.
不 — single pictograph; bird flying upward
Originally a pictograph in oracle bone script, traditionally interpreted as a bird flying up toward the sky and unable to come down, suggesting negation or refusal. Over time it became the standard negation word in Chinese, used before verbs and adjectives to mean 'not'.