A niggardly rich man is someone who is wealthy but extremely stingy and miserly with their money. Some synonyms for this type of person include a penny-pincher, a cheapskate, or a tightwad. They can also be described as a skinflint, a miser, or a Scrooge. These terms are commonly used to describe someone who hoards their wealth and refuses to spend it on anything but the bare minimum. In contrast, a generous rich man is described as a philanthropist, an altruist or a benefactor. They are known for their kindness and generosity, often donating large sums of money to various charities and causes.