To stir up, agitate, cause unrest or excitement in.
To react, using fermentation; especially to produce alcohol by aging or by allowing yeast to act on sugars; to brew.
Something, such as a yeast or barm, that causes fermentation.
A gentle internal motion of the constituent parts of a fluid; fermentation.
A state of agitation or of turbulent change.
A catalyst.
to cause to be more lively or enthusiastic.
to become more lively or enthusiastic.
To cause to be more upright, straighten up
His ears perked up when he heard there would be ice cream.
To become more upright