Rhinestone/ˈraɪnstəʊn/ Definition 1 of 2Pro Tip 1/3Visual Deception Rhinestones mimic diamonds, intended to deceive the eye with their brightness. Her necklace sparkled with rhinestones, catching everyone's attention. Pro Tip 2/3Costume Accessory Often used for costumes because they're inexpensive but flashy. The performer's costume shined with hundreds of colorful rhinestones. Pro Tip 3/3Crafting Material Commonly used in DIY projects to add a sparkly touch to objects. She glued rhinestones onto her phone case for a custom look.