I'd thought we already had a thread on this topic, but the post I remembered was tangential to the topic. Here's what I wrote about "neck of the woods"
"My neck of the woods" simply means my area, my particular environs. The word neck applies to a stretch of coastline that doubles back on itself, I'd say it's a protrusion not prominent enough to be a promontory, or a narrow connective bit of land connecting a small promontory. Sometimes necks are submerged at high tide, and the "promontory" becomes a small island, or simply "rock." On a larger, more continental scale you'd call such a feature an isthmus-- but it usually goes the other way in AE, where people give up on the tongue-twisting borrowed-Greek term and call an isthmus a neck.
As the great forests have long been reduced to isolated island-like stands of woods, I think neck must've come into the language by analogy. A neck connects a protrusion of wooded growth into an upper drainage, just as a neck connects a small promontory to the mainland. Often settlers cleared the upper part of a drainage and left the narrow (neck-like)entry to their particular "holler" overgrown except for the trail or lane, an easily-defended entryway that would be regionally known as someone's particular neck of the woods.
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