not fashionable► out of fashion no longer fashionable - use this especially about clothes and music: · It seems like all the clothes I buy are out of fashion by the time I wear them.go/fall out of fashion: · Rock'n'Roll began in the fifties and has never really gone out of fashion.
► go out especially British to stop being fashionable: · Jogging went out when it was found to be harmful for the joints.· I can't believe you're wearing those shoes -- they went out years ago!
► unfashionable not fashionable - use this especially about people's ideas, beliefs, and way of life: · She lives in an unfashionable part of West London.· Socialism became unfashionable after the collapse of the Berlin Wall.
► uncool spoken informal not fashionable, interesting, or attractive - used especially by young people: · a really uncool place for a holidayit's uncool to do something: · Nowadays it's considered very uncool to wear fur.
► date to gradually become unfashionable, and be replaced with more modern styles, methods, ideas etc: · The trouble with high fashion clothes is that they date very quickly.· Certain styles of music will never date, and will always be popular.
not fashionable or acceptable – used especially by young people: 
Have you seen his shorts? They are just so uncool!