Here's a breakdown:
* Holler: This is a regional term for a hollow or valley, often a narrow, steep-sided ravine.
* Mouth: This refers to the opening or entrance of something, in this case, the holler.
Therefore, "mouth of holler" describes the point where a valley or hollow opens up into a wider area.
Example: "We drove down the mountain road until we reached the mouth of the holler, where the old cabin stood."
Note: The term "holler" can sometimes be used interchangeably with "hollow," although it has a more specific meaning in some regions.