The whole framework of the essay is the finding equivalence for terminologies or terms within technical translation. In this study, from the point of view of terminology studies, the usage of technical terms is the first step for normalizing that the use of understanding technical communication is highly important. The written defines the equivalence as the one- to- one mapping oh characteristics of a concept; however, there are degrees in equivalence like the denotational meaning and connotational meaning and equivalence. Furthermore, the writer describes Catford's theory and his dichotomy of textual versus formal equivalence. The next step taken by the writer is the importance of consistency and variation in lexical choice as a important feature of a good technical translation. In other words, by saying consistency it is meant the avoidance of synonymy in technical texts. Now, there is a problem, in fact, the consistency of technical texts require the avoidance of synonymy, at the same time, some lexical aspects known as lexical cohesions are impossible to reproduce. Therefore, there is a tension between the demand or asking for lexical consistency in technical terms and those of patterns of lexical cohesion across languages.

In the next part of the study, the writer explained a case study which was based on the above- mentioned issue in translation of technical texts. In this study, a kind of text written in German language is translated both in to English and French. Then, the results are discussed. It is proved that the French translator introduced more variation and the English translator introduced less variation.

To sum up, after conducting a piece of research it is said that there is a clash or balance between the consistency within the technical text and the lexical cohesion.