The word "unblocking" refers to removing an obstruction or barrier, allowing progress or flow. The most common antonym for unblocking is blocking, where something is preventing movement or progress. Other antonyms for unblocking include obstructing, hindering, impeding, and stalling, where something causes delay or interference. Conversely, antonyms for unblocking that state a positive action include promoting, accelerating, advancing, and facilitating, all describing ways of making progress easier or faster. Depending on the context, the choice of antonym for unblocking can vary, but all describe varying degrees of opposition towards progress or flow.