つまり + clause

[In other words / That is to say / In short]

Connection: つまり + clause (used at the beginning of a sentence or clause)

Usage: A conjunctive adverb used to restate, summarize, or clarify what was said before in simpler or more direct terms. Can also be used to draw a conclusion from previous statements. Common in both spoken and written Japanese.

Similar expressions:

• 要するに = in short / to sum up (more summarizing)
• すなわち = namely / that is (more formal/academic)
• 言い換えると = in other words (more explicit about rephrasing)

Examples:

彼は社長の息子だ。つまり、将来この会社を継ぐ人だ。(He is the president's son. In other words, he is the person who will take over this company in the future.)

来週の月曜日は祝日です。つまり、三連休になります。(Next Monday is a holiday. That is to say, it will be a three-day weekend.)

彼女は何も言わなかった。つまり、賛成したということだ。(She didn't say anything. In short, that means she agreed.)