Adjective madcap has 1 sense
- hotheaded, impulsive, impetuous, madcap, tearaway, brainish - characterized by undue haste and lack of thought or deliberation; "a hotheaded decision"; "liable to such impulsive acts as hugging strangers"; "an impetuous display of spending and gambling"; "madcap escapades"; (`brainish' is archaic)
Antonym: cautious (indirect, via incautious)
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Noun madcap has 1 sense
- daredevil, madcap, hothead, swashbuckler, lunatic, harum-scarum - a reckless impetuous irresponsible person
--1 is a kind of adventurer, venturer
--1 has particulars: tearaway
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