1The front and back (or front and rear) of something; a spatial relation of before and behind.
車の前後にセンサーが付いていて、駐車の時に安心だ。
The car has sensors on the front and back, which is reassuring when parking.
隊列の前後で連絡を取り合いながら進んだ。
The front and back of the line kept in contact with each other as they moved.
家具の前後を間違えて組み立ててしまった。
I assembled the furniture with the front and back mixed up.
2The time before and after a particular event.
手術の前後は安静にしている必要がある。
You need to rest quietly before and after the surgery.
試験の前後で生徒の表情が全く違った。
The students' expressions were completely different before and after the exam.
引っ越しの前後は何かと忙しいものだ。
The time around a move tends to be busy one way or another.
3Attached after a quantity, time, or age to mean "approximately" or "about that much."
このかばんは一万円前後で買える。
You can buy this bag for around ten thousand yen.
到着は午後三時前後になりそうです。
We'll probably arrive around 3 p.m.
彼女は三十歳前後に見える。
She looks to be around thirty years old.
4The order or sequence of things, or the context/connection between parts.
文章の前後をよく読めば、言いたいことが分かる。
If you carefully read what comes before and after, you'll understand the point.
話の前後がつながらず、意味がよく分からなかった。
The parts of the story didn't connect, so I couldn't quite grasp the meaning.
5The consequences or aftermath resulting from an event.
事件の前後を考えずに行動してしまったことを後悔している。
I regret having acted without thinking through the consequences of the incident.
この決断の前後をしっかり見極める必要がある。
It's necessary to carefully weigh the consequences of this decision.
6Just when something happens, or around that time.
彼が到着したのと前後して、雨が降り出した。
It started to rain just around the time he arrived.
発表の前後、会場はざわめきに包まれた。
Just around the time of the announcement, the venue was filled with murmurs.
7Inversion or reversal of order; things becoming mixed up or out of sequence.
説明の順序が前後してしまい、聞き手を混乱させた。
The order of the explanation got reversed, confusing the listeners.
資料のページが前後していたので並べ直した。
The pages of the document were out of order, so I rearranged them.
8Two or more things occurring at roughly the same time, or one right after another (often used as 前後して).
二人は前後して会場に到着した。
The two of them arrived at the venue one right after the other.
発表と前後して、新製品の予約受付が始まった。
Around the same time as the announcement, pre-orders for the new product began.