na-adjective, noun
Refers to tangled, thorny undergrowth or a dense thicket. Often used in literary or descriptive contexts.
山道はおどろに覆われて進めなかった。
The mountain path was covered in briars and we couldn't go on.
庭の隅におどろが茂っている。
A thicket is growing thickly in the corner of the garden.
The origin is uncertain. The kanji 棘 and 荊棘 both mean 'thorn' or 'briar' and are used for their meaning rather than phonetic value.