Yeast plant Meaning, Definition & Usage

Definitions
  1. (Bot.), the vegetable organism, or fungus, of which beer yeast consists. The yeast plant is composed of simple cells, or granules, about one three-thousandth of an inch in diameter, often united into filaments which reproduce by budding, and under certain circumstances by the formation of spores. The name is extended to other ferments of the same genus. See Saccharomyces.

Webster 1913