When something is described as "gummed up," it usually means that it has become sticky or confined due to buildup or obstruction. Some synonyms for this phrase include clogged, choked, obstructed, impeded, and jammed. Clogged is typically used to describe a blockage caused by an accumulation of material, such as a drain or pipe. Choked and obstructed are often used to describe situations where something is completely or partially blocked, such as a roadway or airway. Impeded is used when something is hindered or slowed down, as in the case of traffic or progress. Finally, jammed is typically used to describe a situation where something is tightly packed and cannot be moved.