bottleneck noun 4verb 2forms 3 noun4 •The narrow portion that forms the pouring spout of a bottle; the neck of a bottle. •(figurative) In traffic, any narrowing of the road, especially resulting in a delay. •(figurative) The part of a process that is too slow or cumbersome due to the lessening of available throughput.It is easy to create entries; processing the paperwork is the bottleneck.The bottleneck in this computer program is the inefficient sorting process; we should replace it with a faster one. •A portion of a bottleneck placed on the finger and used as a guitar slide. verb2 •To slow by causing a bottleneck.The merge bottlenecked the traffic every morning. •To form a bottleneck.The traffic bottlenecked at the merge every morning. formsbottlenecked · bottlenecking · bottlenecks