This idiom describes someone who feels profoundly uncomfortable, awkward, or disoriented in an unfamiliar environment, much like a fish struggling to survive outside its natural aquatic habitat. It conveys a sense of alienation or lack of belonging, often due to cultural, social, professional, or situational differences. The phrase is used to express empathy for someone out of their element or to highlight their struggle to adapt, carrying a sympathetic or descriptive tone. It reflects the universal human experience of navigating foreign contexts, emphasizing the challenges of adjustment and the discomfort of being misplaced, whether temporarily or persistently.

The phrase has ancient roots, traceable to the Latin proverb *piscis ex aqua* (‘fish out of water’), used by Cicero in the 1st century BCE to describe displacement in social or political contexts. In English, it emerged in the 14th century, with Geoffrey Chaucer’s *The Canterbury Tales* (1387) employing ‘lyk a fish out of water’ in *The Monk’s Tale* to depict a monk’s discomfort outside his cloister. John Ray’s 1670 *English Proverbs* recorded the modern form: ‘Like a fish out of water.’ The idiom gained prominence in the 18th century as travel and social mobility increased, reflected in Samuel Johnson’s *Rasselas* (1759), where characters feel alienated abroad. In 19th-century America, it was popularized by Mark Twain’s *A Connecticut Yankee in King Arthur’s Court* (1889), capturing the protagonist’s anachronistic plight. The phrase’s vivid imagery, rooted in the universal struggle of fish on land, and its relevance to cultural exchange ensured its spread across English-speaking regions, from Britain to the Americas and beyond.