英汉词典

1. 粗心的;大意的
    If you are careless, you do not pay enough attention to what you are doing, and so you make mistakes, or cause harm or damage.

careless的近义词

    e.g. I'm sorry. How careless of me...
           对不起,我太不小心了。
    e.g. Some mothers were a bit careless with money...
           有些当妈妈的花钱有点随意。