조차 is equivalent to the English “even” and “to the extent of” such as ” I didn’t even know”. Ex) 1) 그 여자가 제 이름조차 몰랐어요… That girl didn’t even know my name. 2) 생각조차 하기 싫어요. I don’t even want to think about it. There is also 마저. Here is an explanation of differences between 조차 and 마저 From http://chaemii.blogspot.kr/2011/03/blog-post.html "조차" and "마저" can only be used in negative situation. "조차" can be substituted with "마저" but the reverse is not always true. Their main difference is, "조차" can only be used in negative sentence (부정문, 否定文) while "마저" can be used in both negative and positive sentence (긍정문, 肯定文). Ex) 1. 그 학생은 노래조차 못 불러 (O) 2. 그 학생은 노래마저 못 불러 (O) Explanation: In 1 and 2, the negative situation mentioned is the inability to even sing a song properly. Also, both sentences are considered negative sentences because they end with "못 불러". Since both situation and sentence are negative, "조차" and "마저" can be used interchangeably. 3. 추운데 바람조차 부네요 (X) 4. 추운데 바람마저 부네요 (O) Explanation: In 3 and 4, the negative situation mentioned is the wind blowing during cold weather. However, quite different from 1 and 2, 3 and 4 end with "부네요" which makes them positive sentences. Under such circumstance, "조차" cannot be used. What comes after "조차" are always negative things like "못", "않다", "지 않다", "없다", "힘들다", "죽다" etc.