What do you mean of plot in the short story?

Originally, short stories were just that: a story that didn't require many Words to tell. Often the story ended with a surprise twist or drew some moral (De Maupassant, for instance, or O Henry). Many short stories are still written that way (genre stories, for instance: detective, Science Fiction, western, romance, etc.). Like most novels, these stories have a plot with a beginning, a middle, and an end.

Under the influence of Gogol, Chekhov, and Katherine Mansfield the short story changed to be something different from a short novel. Now, the author attempted to capture a moment in the life of a character (or a group of characters) or to create a particular impression in the mind of the reader. The story grew more allusive: it would be hard to describe the "point" of the story. Plot, in the sense of one event leading to another event, leading to some conclusion, was less important and may disappear altogether. In this form, a short story may focus on a wide variety of events without using a plot: a moment that summarizes a character or crystallizes it or proves to be a turning point in a character's life might all be the subject of a short story, for instance.