#observer

• Sighting apparatus — That aims or serves to fix the gaze or attention; an element, factor, or instrument that forces a steady focus. As a noun, it describes a person who stares fixedly, an unwavering observer, or, in an archaic technical sense, a rudimentary sighting device used to guide the trajectory of a weapon or optical apparatus.
• Sighting apparatus — That aims or serves to fix the gaze or attention; an element, factor, or instrument that forces a steady focus. As a noun, it describes a person who stares fixedly, an unwavering observer, or, in an archaic technical sense, a rudimentary sighting device used to guide the trajectory of a weapon or optical apparatus.