The idiom a big fish in a small pond has been in use since the 1880s. An idiom is a figure of speech that is a word, group of words or phrase that has a figurative meaning that is not easily deduced from its literal definition. We will examine the meaning of the expression a big fish in a small pond, where it came from and some examples of its use in sentences.
A big fish in a small pond is someone who is important within his limited sphere, but not in the larger world. For instance, a city councilman would be an important person within that particular city where he may yield power, but would not be important in a neighboring city or in the country as a whole. The idiom a big fish in a small pond may be considered an aphorism, as for most people, it is better to have a small sphere of influence than no sphere of influence at all. Occasionally, the phrase a small fish in a big pond is used to mean someone who is unimportant and powerless. The idiom a big fish in a small pond first appeared in the United States in the 1880s, though it may have been in use long before this time.
In that transition, the stock exchange went from being a big fish in a small pond to being a tiny player among giant developed market exchanges. (The Jerusalem Post)
From his days playing ball an a lightly recruited high-schooler in Oakland to his time as a big fish in a small pond at Weber State through his years with the small-market Portland Trail Blazers, Lillard has had the proverbial chip on his shoulder, always itching to prove doubters wrong. (The Spokesman-Review)