that is to say; in other words~
States a conclusion or restatement from what was just said, meaning 'that is to say' or 'in other words'.
This pattern is used when you take the information you just heard or stated and draw a logical conclusion or rephrase it more clearly. It often appears in conversations when confirming understanding or summarizing. The phrase ということは literally means 'the fact that...' and the 'は' marks it as the topic, so you are saying 'as for that fact, it means...'. It can sound a bit analytical, so it's common in discussions, explanations, or when you're thinking out loud.
For example, if someone says they missed the last train, you might reply 'ということは、今日は帰れないね' meaning 'that means you can't go home today.' It's not just a simple 'so'—it emphasizes the logical step you're taking. You can also use it to restate something in simpler words: '彼は無職だ。ということは、時間はあるということだ' ('He's unemployed. In other words, he has time.')