parsimonious
Very unwilling to spend money or share things; stingy.
Parsimonious means extremely careful and sparing with money or resources, often to the point of being stingy. A parsimonious person might reuse tea bags three times, turn off lights in every room they leave, and refuse to buy new shoes even when their old ones have holes. While being careful with money can be wise, parsimony (the noun form) suggests taking thrift to an extreme that can seem excessive or even miserly.
The word often appears in serious writing to describe someone who's reluctant to spend or give. A parsimonious employer might pay workers as little as possible, or a parsimonious government might refuse to fund important programs to save money. You might read about a character in a novel who lives in a parsimonious way, eating plain meals and wearing threadbare clothes despite having plenty of money saved.
Parsimonious differs from frugal or thrifty, which suggest sensible money management. Being frugal means spending wisely; being parsimonious means barely spending at all. Someone who's parsimonious with praise rarely compliments others, even when they deserve it. Someone who's parsimonious with their time might refuse to help a friend who needs them. The word carries a critical tone, suggesting that the person is holding back more than they should.