In modern research, works dealing with peculiarities of various cultures and the connection between concepts and cultures are becoming more and more topical. British mentality inevitably finds its linguistic representation in British English. This statement is supported by examples from mass-media language. Furthermore, definitions of insularity from authoritative monolingual dictionaries are adduced. It is noted that insularity is manifested in a special, suspicious attitude towards foreigners. As a result, such words as foreign or foreigner evoke negative associations in British peoples minds. However, this is not reflected in lexicographic sources in any way, apart from the fact that the adjectives alien and strange are given as synonyms for the above-mentioned lexical units. The main methods of the research are lexical-semantic, contextual, linguocognitive and discursive analyses. Concrete examples of lexical units which are used in mass media language and reflect British insularity are studied. Linguistically the concept of insularity is represented by lexical units with positive and negative connotations, for example, the adjectives powerful and abrasive, as well as tropes and figures of speech, for instance, metaphors (liberal grit in the unctuous continental oyster) and oxymoron (romantic self-destruction). These lexical means not only confirm that the concept of insularity is an integral part of linguistic and conceptual worldviews of the British but also help the author of the analyzed article to express the idea that unlike other European countries Britain is an example to follow. The research results contribute to the theory and practice of teaching English language and culture and better understanding of the peculiarities of British English.