A situation in which one person has more power, influence, knowledge, or experience than others within a small group. It often implies that the person may not have as much clout in "a bigger pond," i.e., a larger group or arena of some kind. Since she was so popular and well-known within the walls of her small high school, Jennifer was used to being a big frog in a small pond. Once she started attending a large state university, however, she suddenly realized that it would take a lot more effort to make friends. His coarse management style has made it evident that he was used to being a big frog in a small pond. That attitude certainly won't be tolerated by anyone at his new company.