The word "glitter" refers to a shiny, sparkling quality that something possesses. It describes how light reflects off a surface, creating a bright and attractive appearance. For example, when sunlight hits the surface of water, it can create a glittering effect, making the water look as if it's covered in tiny sparkling diamonds.
The term "glitter" comes from the Middle English word "gliteren," which means "to shine." It is derived from the Old English "glitrian," which has similar meanings of shining or gleaming. The word has evolved over time but continues to represent a bright, reflective quality.