Telescopium is a Latin word that means telescope. There are several synonyms for the word telescopium, including spyglass, binoculars, periscope, monocular, field glasses, optical instrument, refractor, reflector, and astronomical telescope. Spyglass refers to a small telescope that is used to observe distant objects. Binoculars consist of two telescopes mounted next to each other, allowing for stereoscopic vision. Periscopes are used to see over or around obstacles. Monoculars are compact and lightweight telescopes that can be easily carried in a pocket or bag. Field glasses are binoculars that may have a higher magnification power. Refractor and reflector telescopes are two types of astronomical telescopes used to observe celestial objects.