「今週」 means this week, referring to the current week you are in. It's useful for talking about plans, events, or tasks scheduled for the ongoing week. It helps to organize your immediate schedule.

今(いま)現在(げんざい)進行中(しんこうちゅう)の週(しゅう)を意味(いみ)します。今週(こんしゅう)の予定(よてい)や出来事(できごと)を話(はな)すときに使(つか)います。