The term 'block up' can be defined as to STOP, CLOG, OCCLUDE, DAM, or CHOKE. To 'STOP' something is to prevent it from continuing or progressing, while to 'CLOG' something is to fill it with an obstruction that prevents the flow of a liquid or gas. To 'OCCLUDE' something is to block or close off a passage, while to 'DAM' something is to build a barrier across a river or other body of water. Finally, to 'CHOKE' something is to restrict the flow of air or other gases. All of these terms refer to the act of blocking something up, either physically or figuratively.