adj. 25B6; adjective
dense thorny undergrowth : PRICKLY, spiky, barbed, spiny, sharp; technical spinose, spinous.
the thorny subject of confidentiality : PROBLEMATIC, tricky, ticklish, delicate, controversial, awkward, difficult, knotty, tough, taxing, trying, troublesome; complicated, complex, involved, intricate; vexed; informal sticky.