Synonyms for Reckless (same or very similar meaning)
WordNet sense 1 (characterized by careless unconcern):
heedless
WordNet sense 2 (marked by defiant disregard for danger or consequences):
foolhardy, heady, rash
WordNet sense 3 (fearless and daring):
bold
WordNet sense 4 (marked by lack of attention or consideration or forethought or thoroughness; not careful):
careless
From the ODE community, based on WordNet
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