foolhardiness 

英汉解释

n. 有勇无谋；蛮勇；愚勇

同义词

n. rashness，recklessness

参考例句

1. Greed and foolhardiness were not invented just recently.
贪婪和愚勇，并不是今天才出现的。
2. Courage in excess becomes foolhardiness, affection weakness, thrift avarice.
勇之过度则蛮，爱之过度则为宠，俭之过度则为贪。
3. Courage in excess becomes foolhardiness, affection weakness, thrift avarice.
勇敢过度，即成蛮勇，感情过度，即成脆弱，俭约过度，即成贪婪。

英英解释

n.
  1. the trait of giving little thought to danger

网络释义

foolhardiness
愚勇; 有勇无谋; 蛮勇;