the.com/thicket

nature's barbed wire, growing thorns specifically to ruin your shortcut and shred your shins

means A dense, tangled growth of shrubs, bushes, or small trees, too thick to walk through easily.

from From Old English thiccet, formed from thicc ("thick") — so at its root it's simply "a thick place," the same word you use for soup or a stack of books, applied to vegetation that has crowded in shoulder to shoulder. A cousin of the modern "thick" through the shared Germanic stock.

animal fortress: rabbits and birds nest where predators can't follow
old english: name literally means thick-set place of growth
fire fuel: dense underbrush turns wildfires into unstoppable infernos
legal metaphor: thicket of regulations describes hopeless bureaucratic tangles
hedge ancestor: medieval thickets became deliberate defensive boundaries

for instance

sherwood forest — dense woodland in nottinghamshire, england where robin hood allegedly hid among the trees

amazon rainforest understory — impenetrable layer of vegetation 20-60 feet above ground in the world's largest tropical thicket

everglades sawgrass — 2.7 million acre thicket of sharp-edged grass in florida with depths up to 11 feet