Is there a word for words that change pronunciation when prefix or suffix is added?

There isn't a single, universally accepted word for words that change pronunciation when a prefix or suffix is added. However, there are a few terms that come close, depending on the specific aspect you're focusing on:

* "Stress-shift words" or "accentual words": This term refers to words where the stress (the emphasis) changes when a prefix or suffix is added. For example, "import" vs. "important."

* "Morphophonological words": This term describes words where the sound changes based on morphological changes (adding prefixes or suffixes). This is a broader term that encompasses both stress shifts and other sound changes, such as vowel changes or consonant changes.

* "Irregular words": While not a specific term for this phenomenon, some might consider words with unpredictable pronunciation shifts as "irregular." For example, "sign" vs. "signature" or "decide" vs. "decision."

Ultimately, the best term depends on the specific context and what aspect of the pronunciation change you are emphasizing.