To save money by not wasting it on things you dont actually need.
wise or judicious in practical affairs; sagacious; discreet or circumspect; sober.
careful in providing for the future; provident: a prudent decision.
economical in use or expenditure; prudently saving or sparing; not wasteful: What your office needs is a frugal manager who can save you money without resorting to painful cutbacks. Synonyms: thrifty, chary, provident, careful, prudent, penny-wise, scrimping; miserly, Scotch, penny-pinching. Antonyms: wasteful, extravagant, spendthrift, prodigal, profligate.
Mum: You really need to start saving money, you need to be really frudent at Christmas.
Mum: Yeah, Frugal and Prudent, Frudent.
Me: Mum! You just invented a word! I'm putting that on Urban Dictionary!!