Princeton students started calling their grounds a Latin word for an open field.
The Latin word campus meant an open field, a flat expanse of ground used for military exercises, public gatherings, or agriculture. The Campus Martius (Field of Mars) in ancient Rome served as a drill ground for soldiers and a space for elections and religious ceremonies.1
The word entered American English in the 1770s, when students at the College of New Jersey (later Princeton University) began using it to describe the grounds of their institution.2 The choice was deliberate. By borrowing a Latin term, the students linked their modest colonial college to the classical tradition.
The usage spread slowly. By the mid-nineteenth century, campus had become the standard American term for university grounds. In British English, the word was uncommon until the twentieth century. British universities used "grounds" or specific place names instead.3
The Latin word for an open field acquired a specific and narrow meaning in English. A campus was not merely any grounds. It was the enclosed, curated space of a learning institution, a place set apart from the surrounding town for the purpose of education.
By the late twentieth century, the word had jumped beyond education. Technology companies built "corporate campuses" designed to replicate the university experience, complete with cafeterias, fitness centers, and open green spaces. Apple, Google, and Facebook invested billions in campus architecture that blurred the boundary between workplace and university.4
The migration of the word from military drill ground to university lawn to corporate headquarters traced a specific cultural trajectory. The Roman campus trained soldiers for the state. The American campus trained students for professions. The corporate campus trained workers to feel that their company was worth never leaving.