The state or quality of being arduous; steepness, difficulty.
An obstacle or impediment.
A separation between two areas of the body where specialized cells allow the entry of certain substances but prevent the entry of others.
A martial exercise of the 15th and 16th centuries.
The lists in a tournament.
A structure that bars passage.
A node (in government and binding theory) said to intervene between other nodes A and B if it is a potential governor for B, c-commands B, and does not c-command A.
A boundary or limit.
To block or obstruct with a barrier.