From the point of view of applied linguistics, terminology is a discipline subject to discourse variation. It is considered a functional language subsystem characterized by designated specialized concepts. The so called variety principle confronts the traditional premises set by Wüster. Their object was terminological standardization based on the idea of uniform terminological units regarding time, space and social environment. This clear-cut situation is threatened by the complexity of the linguistic reality. The proposal described here takes root on the terminological diversity respecting the aforementioned aspects. There has been a shift from an unitary world view towards a vision characterized by multidisciplinarity. Consequently, the units used to express specialized knowledge will show a diversity which must be studied through linguistic models.