Terminology is one of the main industries of specialized communication. This paper proposes an account of how metaphors and terms interact when students learn scientific concepts and the linguistic processes that drive designation when researchers try to name emerging concepts. Selected tools of metaphor theory (assumptive frameworks, conceptual blending, and source and target fields) will be presented along with terminological tools including concept description and term definition which, if only theoretically, lead to monosemous, field-restricted terms. (LLBA 2000, vol. 34, n. 4)