Fashion trends are styles, clothing, colors, accessories, or ways of dressing that become popular among many people during a particular period of time.
For example, when many people start wearing baggy jeans, oversized shirts, or Y2K-inspired outfits, these styles can be considered fashion trends.
Simple definition for your presentation:
Fashion trends are popular styles and clothing choices that become widely accepted and followed by people at a certain time.
Fashion trends can be influenced by social media, celebrities, influencers, designers, music, movies, and popular culture.