1.
inside and outside
Both the interior and exterior of something.
建物の内外を点検する。
To inspect both the inside and outside of a building.
家の内外を掃除した。
I cleaned both the inside and outside of the house.
車の内外を洗った。
I washed both the inside and outside of the car.
会社の内外で評判が良い。
They have a good reputation both inside and outside the company.
2.
domestic and foreign; home and abroad
Both within a country and internationally.
国内外から注目を集めている。
It's attracting attention from both home and abroad.
内外の情勢を分析する。
Analyze domestic and international conditions.
内外の企業が参加した。
Both domestic and foreign companies participated.
内外の投資家に人気がある。
It's popular among domestic and foreign investors.
内外から批判を受けた。
It received criticism from both home and abroad.
3.
approximately
About (a certain number); roughly.
参加者は100人内外だった。
There were approximately 100 participants.
費用は50万円内外だ。
The cost is approximately 500,000 yen.
1時間内外で着く。
It takes approximately one hour to arrive.
30歳内外の人。
People around 30 years old.
重さは1キロ内外だ。
The weight is approximately one kilogram.
200名内外が集まった。
Approximately 200 people gathered.
内外 combines 内 (inside) + 外 (outside), with three distinct uses.
MEANINGS:
1. Inside and outside (physical): 建物の内外
2. Domestic and foreign: 国内外
3. Approximately (with numbers): 100人内外
COMMON EXPRESSIONS:
- 国内外: domestic and international
- 社内外: inside and outside the company
- 内外の情勢: domestic and international conditions
- 〜内外: approximately (formal register)
NOTE ON "APPROXIMATELY":
The "approximately" meaning is more formal than 約 or ぐらい. Often seen in news and business contexts.