Collins COBUILD Advanced Learner's English Dictionary - vanishing point

(vanishing points) 1. The vanishing point is the point in the distance where parallel lines seem to meet. The highway stretched out ahead of me until it narrowed to a vanishing point some miles away. N-COUNT: usu sing 2. If you say that something has reached vanishing point, you mean it has become very small or unimportant. By 1973, this gap had narrowed almost to vanishing point... N-UNCOUNT