A paronychia is an infection of the skin that surrounds a toenail or fingernail. Acute paronychia â This usually appears as a sudden, very painful area of swelling, warmth and redness around a fingernail or toenail, usually after an injury to the area.
Definition of 'reflector'. reflector (rÉªflektÉÊ³ ) A reflector is a small piece of specially patterned glass or plastic which is fitted to the back of a bicycle or car or to a post beside the road, and which glows when light shines on it. A reflector is a type of telescope which uses a mirror that is shaped like a ball.
A reflecting telescope (also called a reflector) is a telescope that uses a single or combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century, by Isaac Newton, as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter objectives.