1. hastiness Rashness applies to the actual rushing into danger without counting the cost; temerity denotes the needless exposure of oneself to peril which is or might be clearly seen to be such. Rashness i Synonyms: temerity, audacity, heedlessness, presumption, foolhardiness, over-confidence, rashness, hardihood, precipitancy, recklessness, hastiness, precipitation, venturesomeness Antonyms: care, circumspection, cowardice, hesitation, timidity, wariness, caution