Bu pretty much means don't. Ex. Wo Bu Xi Huan Mao.
bu dong mean "I don't understand"
no
no
Bu means NO
I don't know what exactly charasters you mean by "bu". There are too many characters for "bu". Each has different meanings.
I believe you mean: 对不起 Duì bù qǐ
the most likely meaning is "no" but it could also mean 'cloth' or 'step' depending on the context or tone.
The translation for 'no' into Chinese is '不' or 'bu'.
pao bu
Bu Zhengcheng
Bu (4)Xie (4)Xie (4) but that's kinda simple. If you mean when some one offers you something then...bu(2)yong(4)le(4) Xie(4) Xie (4)
不 but in pinyin it's bu