There isn't one single, universally accepted scientific term for "yeast." Instead, it's a general term that refers to a large group of unicellular fungi.

Here's why:

* Taxonomic classification: Yeast isn't a single species, but rather a group of fungi belonging to different genera. These genera include *Saccharomyces*, *Candida*, *Cryptococcus*, and many others.

* Diverse functions: While most people think of yeast in terms of baking and brewing, they are a very diverse group with various roles in the ecosystem.

So, when talking scientifically, you'll need to be specific about the type of yeast you're referring to. For example:

* Saccharomyces cerevisiae: The most common type of yeast used in baking and brewing.

* Candida albicans: A type of yeast found in the human body that can cause infections.

* Cryptococcus neoformans: A type of yeast that can cause serious infections in people with weakened immune systems.