Definition of investor noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. We use cookies to enhance your experience on our website, including to provide targeted advertising and track usage. Why Is it Important to Invest Money for Retirement ... Dec 12, 2019 · The reason you might not want to start saving for your retirement at a young age -- quality of life -- is the exact reason you should. When you first start earning money, you want to enjoy it, spending it on things and activities that let you have some fun, rather than just using your money to pay bills.