B1[C or U]the ability to form pictures in the mind: My younger son has a very vivid(= active) imagination.I can never make up stories - I have absolutely no imagination.For some reason the story captured/caught the imagination of the public (= made them very interested).It couldn't by any stretch of the imagination be described as a (= it is certainly not a) beautiful city.There's a sex scene in the film which apparently leaves nothing to the imagination (= shows sexual parts of the body very clearly).Imagining and conceiving›[U]something that you think exists or is true, although in fact it is not real or true: Was she paying him a lot of attention or was it just my imagination?Is it my imagination or is David behaving strangely at the moment?DreamingB1[U]the ability to think of new ideas: It's a job that needs someone with a bit of imagination.Imagining and conceiving