Lacking good style or any style at all.(adjective)
Lacking a style (stalk structure).(adjective)
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Use "styleless" in a sentence
"Now I feel like the number of slipper wearers are gaining strength... and that when my husband scowls at my 'styleless' choice of footwear, I can say "Well other people wear them too!""
"I just have a hard time believing a plane could take a skyscraper down demolition styleless than a minute ago via web Favorite Retweet ReplyRashard MendenhallR_Mendenhall"
"In their styleless rubber-soled brogans, bad haircuts, and generic domestic sedans, they looked as out of place as someone on food stamps."