E-learning content is frequently designed with a single source language in mind. When this content is later localized, translation does not introduce instability. Instead, it exposes assumptions that were never tested beyond the original language.

Terminology drift rarely appears as an explicit error. Individual terms may be translated correctly in isolation, yet their meaning shifts gradually across modules, languages, and time. In multilingual e-learning systems, terminology functions as connective tissue. It links concepts across lessons, assessments, interfaces, and documentation. When terminology drifts, the system remains operational, but conceptual coherence weakens.