Monoglottism (Greek μόνοσ monos, "alone, solitary", + γλώττα glotta, "tongue, language") or, more commonly, monolingualism or unilingualism is the condition of being able to speak only a single language, as compared to multilingualism. In a different context "unilingualism" may refer to a language policy which enforces an official or national language over others.
Monolingual or unilingual is also said of a text, dictionary, or conversation written or conducted in only one language, and of an entity in or at which a single language is either used or officially recognized (in particular when being compared with bilingual or multilingual entities or in the presence of individuals speaking different languages). Note that monoglottism can only refer to not having the ability to speak several languages. Monolingual speakers are outnumbered by multilingual speakers in the world's population.
Romaine (1995) pointed out in her book Bilingualism that it would be weird to find a book titled Monolingualism. This statement reflects the traditional assumption that linguistic theories often take on: that monolingualism is the norm. Monolingualism is thus rarely the subject of scholarly publications as it is viewed to be an unmarked or prototypical concept where it has the sense of being normal and multilingualism is the exception.
Also the monolingualism assumption is often the view of monolinguals who speak a global language, like the English language. Crystal (1987) said that the monolingualism assumption is adopted by many in the Western societies. An explanation provided is by Edwards who (2004) claimed that evidence of the "monolingual mindset" can be traced back to 19th century Europe when the nation was rising and a dominant group had control and the European mindsets on language were carried forth to its colonies, further perpetuating the monolingual mindsets.
Another explanation is that the nations who speak the English language are both “the producers and beneficiaries of English as a global language” and the populations within these countries tend to be monolingual.