Wiktionary
briar-patch
n. 1 (context literally English) A dense thicket of thorny plants; ground made impassible by the impenetrable overgrowth of prickly vegetation.“briar patch” listed in '''Webster’s New Millennium™ Dictionary of English''', Preview Edition (v. 0.9.7), Copyright © 2003–2009 Dictionary.com, LLC 2 (context figuratively English) An intellectual or philosophical issue abounding with seemingly unresolvable problems; a theoretical quandary or impasse.