Spotlight filter is a type of photographic filter that is used to create a spotlight effect on the subject of a photograph. It is also known as a starburst filter, and is made up of a series of thin lines radiating from the center of the filter. The filter is usually made of GEL, which is a three-letter word in this crossword puzzle. GEL filters are often used in portrait photography to create a dramatic effect, and can also be used to create a sunburst effect when shooting landscapes.