thriftless (adjective) improvident: careless, spendthrift
Sinonime: extravagant,
heedless,
imprudent,
inconsiderate,
lavish,
negligent,
prodigal,
profligate,
profuse,
reckless, shiftless, shortsighted,
thoughtless, thriftless, uneconomical, unthrifty,
wastefulAntonime: careful,
miserly, provident,
thrifty