See snag in Webster's New World Roget's A-Z Thesaurus II
noun
Something that impedes or prevents entry or passage:
bar, barricade, barrier, block, blockage, clog, hamper, hindrance, hurdle, impediment, obstacle, obstruction, stop, traverse, wall. See help, openA tricky or unsuspected condition:
rub. (Informal) catch. See limited
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