one-horse (城镇)极小的，闭塞落后的；(比赛)一骑绝尘的，胜负分明的

【例句】
Would you want to live in a small, one-horse town for your whole life?
你想在一个闭塞落后的小镇上过一辈子吗？

The city was a gray, drab, one-horse town where the main means of transportation was the bicycle.
那时这个城市是一个灰色、乏味、设施简陋的城市，主要交通工具是自行车。