(a.) Lacking foresight or forethought; not foreseeing or providing for the future; negligent\; thoughtless; as, an improvident man.

brash brazen brazenfaced careless extravagant feckless grasshopper happy-go-lucky headlong heedless hubristic impetuous imprudent impudent impulsive incautious indiscreet injudicious insolent lavish negligent overbold overcareless overconfident oversure overweening prodigal profligate profuse rash reckless shiftless short-sighted spendthrift temerarious thoughtless thriftless unchary uneconomical unmindful unproviding unthinking unthoughtful unthrifty unwary wasteful