termo

Termo is a word used in Portuguese and other Romance languages with several related senses. As a noun, it commonly denotes a term or expression—the specific word or phrase used to denote a concept in speech or writing. In mathematical or linguistic contexts, termo can also refer to a summand or unit of a larger expression, such as a term in an algebraic sum.

In scientific and technical vocabulary, termo also serves as a productive combining form to indicate heat or temperature. This heat-related prefix appears in many terms describing thermal phenomena or devices, such as termodinâmica (thermodynamics), termografia (thermography), termometria or termômetro (thermometer), and termostato (thermostat). The prefix is widespread in Portuguese and other languages, enabling a large set of temperature- and heat-related terms.

Etymology reflects the two main senses. The standalone sense meaning “term” or “expression” derives from Latin terminus, through a natural evolution in the romance languages. The prefix meaning “heat” or “temperature” traces to Greek thermos, adapted into the Romance languages as termo- or therm- in various technical terms. This distinction helps explain why termo can refer to a word in ordinary discourse while also appearing in scientific terms that describe warmth, heat transfer, and thermal systems. Overall, termo is a versatile term with both lexical and productive prefix uses in the modern lexicon.