something that obstructs, blocks, or closes up with an obstacle or obstacles; obstacle or hindrance

obstructions to navigation.

an act or instance of obstructing.

the state of being obstructed.

the delaying or preventing of business before a deliberative body, esp. a legislative group, by parliamentary contrivances.

noun

aid , assistance , boost , help , promotion , support

noun

bar , barricade , barrier , block , blockage , blocking , booby trap * , check , checkmate * , circumvention , difficulty , gridlock * , hamper , hindrance , hurdle , interference , jam * , lock , monkey wrench * , mountain * , restraint , roadblock * , snag , stop , stoppage , stumbling block * , trammel , trouble , wall , clog , impediment , obstacle , traverse , blockade , dam , delay , encumbrance , gridlock , hitch , restriction , roadblock , stumbling block