When it comes to describing "line vision", there are several words or terms that can be used interchangeably, such as "straight-sighted", "clear-eyed", "keen-eyed", "blazing-eyed", and "focused". Additionally, some people may refer to this kind of visual quality as "laser-sharp", which connotes a high level of precision and accuracy. Many of these words are used to describe someone who has a strong and unwavering focus, especially when it comes to a goal or task at hand. Overall, the synonyms for "line vision" all convey the same idea of someone who is alert, attentive, and has a steadfast vision.