Something or someone that departs from common sense or normal social standards; unconventional, eccentric, or outrageous behavior/ideas.
彼の提案はあまりに常識はずれで会議は混乱した。
His proposal was so outlandish that the meeting became chaotic.
常識はずれの行動は周りの人を困らせることがある。
Unconventional behavior can cause trouble for the people around you.
そんな高い服を着るのは常識はずれだとは言わないが、場違いかもしれない。
I wouldn't call wearing such expensive clothes outrageous, but it might be inappropriate for the occasion.