In recent decades, there has been a revolution in expert knowledge due to the emergence of new concepts and, consequently, new terms. Thus, general vocabulary has gradually enlarged with terms traditionally limited to specialised discourse. This fact has not been ignored by the editors of general dictionaries, which include more entries in order to meet their users’ demands. In addition, expert knowledge is usually produced in the English language. However, in a globalised world, the need to transfer terms to other languages such as Spanish has emerged. General bilingual dictionaries are increasingly used to solve the difficulties that arise for users in the transference of specialised knowledge into other languages; however, this tool is not the most suitable when making decisions about the equivalents of specialised terms in other language. Compound specialised vocabulary in general bilingual dictionaries can become an obstacle for users. Given the lack of research in English and Spanish bilingual lexicography, in this paper, we try to acquire an approximation of the treatment of the aforementioned units made up of two or more words in two of the most prestigious general bilingual dictionaries in English and Spanish. From our findings, we hope to obtain relevant data that emphasise the need to improve the standard of information gathered in these reference works and implement the searching procedures used by translators and interpreters.