Unusual or unconventional in a way that is a bit eccentric or original; often used before a noun to modify it.
彼は一風変わった考え方をする。
He has an unconventional way of thinking.
その店は一風変わったメニューが人気だ。
That restaurant is popular for its eccentric/unconventional menu.
一風変わったアイデアが会議を盛り上げた。
An original/unconventional idea livened up the meeting.