This describes a combination of many different individual elements of styles, themes, mediums or inspirations pooled from many sources. It can refer to musical tastes, dress sense, interior design...many things.
She has an ecletic sense of style, today she wears biker boots, pink fishnet stockings, a pencil skirt, a military jacket, a baseball hat, a my little pony t-shirt and a dunlop bag covered in badges from all her favourite bands from ABBA to Kooks
Adjective used by artsy, liberal journalist types to describe just about any album ever produced. A record is particularly "electic" if its tracks vary between criticizing the world's power structures, commiserating about yucky, yucky girls, or talking about all the randomness that makes live "ever so worth living." In other words, it's about giving credence to incoherence.
Artsty journalist: This new album is so eclectic.
Reader: You always say that.