a big fish in a small pond, A person who is important or influential in a small group or organization.
fish out of water, A person who feels uncomfortable or out of place in a particular situation.
Word Origin
Language
Old English
Original word
fisc
Originally meant
an aquatic animal
Background
The word 'fish' comes from the Old English 'fisc', which is related to similar words in other Germanic languages. It has been used in English since before the 12th century to describe aquatic animals.