Oxbridge is a composite of the University of Oxford and the University of Cambridge which are most famous in England and the term is now used to refer to them collectively, often with implications of perceived superior intellectual or social status. Oxbridge can be used as a noun referring to either or both universities or as an adjective describing them or their students.

Although both universities were founded more than seven centuries ago, the term Oxbridge is relatively young. In William Thackeray's novel Pendennis, published in 1849, the main character Pendennis wants to attend the fictional College, Oxbridge, but failed. According to the Oxford English Dictionary, this is the first recorded instance of the word. Virginia Woolf used it, citing Thackeray, in her 1929 essay A Room of One's Own. By 1957 the term was used in the Times Educational Supplement and in Universities Quarterly by 1958. Thackeray's Pendennis also introduced the term Camford as another combination of the university names, but this term has never achieved the same degree of usage as Oxbridge.

Oxbridge is often used as shorthand for characteristics that the two institutions share. Firstly, they are the two oldest universities in continuous operation in England. Both were founded more than 800 years ago, and continued as England's only universities until the 19th century. Between them they have educated a large number of Britain’s most prominent scientists, writers and politicians, as well as noted figures in many other fields. Besides, they have established similar institutions and facilities such as printing houses, botanical gardens, museums, and debating societies. In addition, both universities comprise many buildings of great beauty and antiquity，sited on level terrain ideal for cycling, near slow- moying rivers suitable for rowing and punting. At each of the universities there is a college which has a Bridge of Sighs”，although neither resembles the original Bridge of Sighs in Venice.

Oxford and Cambridge also share a common collegiate structure: each university is composed of more than 30 autonomous colleges, which provide the environments in which groups of students live, work and sleep. Applicants must choose a specific college when applying to Oxford or Cambridge, or allow the university to select one for them, as all undergraduate and graduate students must be a member of one of the university colleges. All Oxbridge colleges are part of the university, and students studying the same subject are given lectures together, irrespective of which college they attend.

Competition between Oxford and Cambridge also has a long history, dating back to around 1209 when Cambridge was founded by scholars taking refuge from hostile townsmen in Oxford.