本文全面回顾传统术语定义的历史背景和理论基础,充分肯定它在术语学奠基和发展中尤其在已有的术语标准化等工作中的积极作用。但通过实例,我们指出传统术语定义的局限性,提出崭新的基于知识本体的术语定义,旨在抛砖引玉,把长期囿于名词术语的传统术语学扩展成一种面向各种专业知识的更广泛的语言表达的术语学理论。 This article reviews the historical background and theoretical basis of the definition of traditional terms in an all-round way, and fully affirms its positive role in standardizing and terminating the existing terminology, especially in the foundation and development of terminology. However, by way of example, we point out the limitations of the definition of traditional terms and put forward a new definition of terms based on ontology. This article aims to extend the traditional terminologies that have long been used in terminology to a broader language for various kinds of professional knowledge Terms of Expression Theory.