거꾸로 + verb (거꾸로 입다/들다); 거꾸로 말하면 = conversely
upside down, backwards, inside out; the other way around
Example
동생이 옷을 거꾸로 입고 학교에 갔어요.
My little brother went to school with his clothes on backwards.
Word parts
Related to the verb 거꾸러지다 'to fall headlong'.