The phrase **"burgeoning hypothesis"** refers to a **new or rapidly developing idea or explanation** that is gaining attention or interest but is still in its early stages of exploration or validation.

### Example in a sentence:

> The burgeoning hypothesis that the cerebellum plays a role in emotion regulation is reshaping our understanding of neuropsychiatric disorders.

### Breakdown:

* **Burgeoning** = growing quickly, expanding
* **Hypothesis** = a proposed explanation made on the basis of limited evidence, subject to further investigation

It’s often used in academic or scientific contexts to signal that a concept is **emerging** and **gathering preliminary support**, but has not yet been fully tested or widely accepted.