(chiefly US, in negative constructions) To know something, even if only a little, about. / (chiefly US, idiomatic) To know nothing, or almost nothing, about.

(intransitive, informal) To be knowledgeable in a particular field.

(idiomatic) Alternative form of wouldn't you know it

Used to speculate about a slight possibility.

(of an activity) designed so that participants get to know each other.

Alternative form of know one's own mind

(idiomatic) To be knowledgeable about, and competent at, a particular subject or task.

Alternative form of God knows (“it is unknown to people”)

(informal) I know; I am very familiar with it (some stated fact).

Alternative form of know what is what