(firearms) The distance between the front and rear sights of a firearm.

(firearms) On some rifles, a type of sight where the shooter looks through a small aperture on the rear sight.

(literally) Not accessible to view. / (idiomatic, of a goal, aspiration, etc) Not yet attainable. / (dated, idiomatic, colloquial) Superb, excellent. / (idiomatic, colloquial) Very expensive.

(idiomatic) Not having seen the object beforehand.

A straight line along which an observer has a clear view. / (weaponry) The line which passes through the front and rear sight, at any elevation, when they are sighted at an object.

Alternative form of eyesight

(music) To perform a musical piece while reading it for the first time, without rehearsal.

A person who is able to sightread.

plural of sight-reader

A triangle at an intersection, formed by the two roads or rights-of-way and a third line, which must be kept clear of obstructions such as hedges so that people in one road can see cars approaching on the other.