but still; and yet; even so
A conjunction meaning 'but still' or 'even so', used to acknowledge a previous point and state that something remains true despite it.
それでも is a conjunction that links two sentences or clauses, showing that the second statement holds true despite the first. It is similar to saying 'even so' or 'but still' in English. For example, if someone says it is raining, you might reply with それでも出かけます (Even so, I'll go out). It emphasizes contrast and persistence.
This word is common in both spoken and written Japanese, and is used at N4 level. It is not too formal, but it is often used in reasoned arguments or to express determination. You can use it in conversation with friends or in essays, but in very casual speech, people might just say でも or それでも is fine too.
Note that それでも is a single word, not to be confused with それで (and so) which indicates cause and effect, or でも (but) which is a simpler contrast. それでも specifically implies that the second part is surprising or strong despite the first.