The prudent man rule is a well-known legal principle that requires fiduciaries to exercise reasonable care, skill, and caution in managing investments. However, there are several synonyms for this rule that are commonly used. For example, the prudent investor rule, the prudent person rule, and the duty of prudence all refer to the same legal concept. These terms are often used interchangeably in legal and financial settings. Essentially, the rule is designed to protect investors and ensure that fiduciaries act in their best interest. Regardless of the specific terminology used, the prudent man rule is a fundamental principle of modern investment law.