operation (n.)

In FORMALIZED analyses, a term normally used in its general mathematical sense of a FUNCTION whose ARGUMENTS are all drawn from the same set. In less formal analyses, it is often used more loosely to refer to any change or PROCESS performed on a linguistic REPRESENTATION. For example, in GRAMMAR, the relationship between present and past TENSE in English can be described as an operation which adds the SUFFIX -ed to the STEM, as in walk⇒ walk+-ed. RULES are one kind of formal operation.