reckless

形容词 reckless:

1. marked by defiant disregard for danger or consequences
   同义词：foolhardy, heady, rash
2. characterized by careless unconcern
   同义词：heedless

1. Courage, especially when reckless.
   蛮勇勇气，尤指不顾后果的勇气
2. He's a reckless driver.
   他是个鲁莽的司机。
3. He's quite reckless of his own safety.
   他完全不顾及自己的安全。
4. His brother is a reckless gambler.
   他的弟弟是个不计后果的赌徒。

reck.less

adj.（形容词）

Heedless or careless.
粗心的：不注意的或粗心大意的
Headstrong; rash.
鲁莽的：草率的；莽撞的
Indifferent to or disregardful of consequences:
不顾后果的：对后果不关心或忽视的：
例句：
a reckless driver.
横冲直撞的司机

来源：
Middle English reckeles
中古英语 reckeles
from Old English rôcelôas * see reg-
源自 古英语 rôcelôas *参见 reg-

【引伸】
reck.lessly
adv.（副词）
reck.lessness
n.（名词）
<参考词汇><同义词>reckless,rash,precipitate,foolhardy,temerariousThese adjectives are compared as they mean given to or marked by unthinking boldness.
当这些形容词都表不加思考的鲁莽的意思时，常把它们进行比较。
Reckless suggests brazen indifference to or defiant disregard for consequences:
Reckless 指对后果厚颜无耻的冷漠或轻蔑的忽视：
例句：
.James . . . became the fiercest and most reckless of partisans. (Macaulay).
.詹姆士…变成了一个最鲁莽且不顾后果的党徒. （麦考利）。

Rash implies haste, impetuousness, and insufficient consideration:
Rash 暗指匆忙、冲动且没有足够考虑的：
例句：
.Take calculated risks. That is quite different from being rash. (George S. Patton).
.精细估算后再去冒这个险。这与鲁莽大大不同. （乔治·S·巴顿）。

Precipitate connotes headlong haste without due deliberation:
Precipitate 暗示没有审慎考虑的轻率匆忙：
例句：
.destroyed in a precipitate burning of his papers a few days before his death. (James Boswell).
.在临死前的几天中他匆忙地烧毁了文件. （詹姆士·鲍斯韦尔）。

Foolhardy implies injudicious or imprudent boldness:
Foolhardy 暗指不明智的或不谨慎的莽撞：
例句：
One of the hostages was foolhardy enough to try to wrest the gun from the hijacker`s hand.
有一个人质莽撞地企图去夺劫机者手中的枪。

Temerarious suggests reckless presumption:
Temerarious 指不顾后果的傲慢：
例句：
.the temerarious use of Christian names. (H.G. Wells).
.傲慢地使用教名. (H·G·威尔斯）