Looking up...
無防備
mubōbi
defenseless
彼女は無防備な笑顔を見せた。
She showed a defenseless smile.
formal
lacking protection or defense against potential harm or danger; vulnerable.
この建物は防犯対策が無防備だ。
This building has no security measures.
無防備な状態で外出するのは危険だ。
Going out in a defenseless state is dangerous.
informal
naive or trusting to the point of being easily taken advantage of.
彼は無防備な性格で、簡単に信じてしまう。
He’s so naive that he believes anything easily.
Pro Tip
Avoiding Misuse
無防備 is often used to describe a person's state or condition, not an action. Use 防備する (bōbi suru) for the verb 'to defend' or 'to guard.' Example: 家を防備する (ie o bōbi suru) = 'to defend the house.'
Word Origin
Composed of 無 (mu, 'without') + 防備 (bōbi, 'defense/preparedness'). Literally means 'without defense,' reflecting the absence of protective measures or vigilance.
Usage Notes
Commonly used in both physical (e.g., security, safety) and social contexts (e.g., naivety, trustworthiness). Often implies a lack of caution that could lead to harm or exploitation.
Word Breakdown
無
without
prefix防備
defense/preparedness
noun和英辞典