a situation in which there are so many cars in the streets of a town that the traffic cannot move at all 市区交通大堵塞 It’s gridlock between 6.30 and 9.00. 六点半到九点之间交通堵塞。 The protest march created gridlock. 抗议游行造成交通瘫痪。 roads that are prone to gridlocks 容易出现交通堵塞的道路
(usually in politics 通常用于政治 a situation in which people with different opinions are not able to agree with each other and so no action can be taken 僵局（因意见分歧而无法采取行动）
Word Origin1980s (originally US): from grid (in sense (1)) + lock ‘become rigidly fixed’.