分度器(ぶんどき)

ぶんどき
noun
protractor
1. protractor
A tool used for measuring and drawing angles, usually semicircular with degree markings.
分度器(ぶんどき)で角度(かくど)を測(はか)る。
To measure an angle with a protractor.
分度器(ぶんどき)を使(つか)って60度(ど)の角(かく)を描(か)く。
To draw a 60-degree angle using a protractor.
分度器(ぶんどき)と定規(じょうぎ)を持(も)ってきてください。
Please bring a protractor and ruler.

分度器(ぶんどき) is a protractor, a semicircular tool marked in degrees used for measuring and drawing angles.

ETYMOLOGY:
分度(ぶんど) (dividing degrees) + 器(き) (instrument).

COMMON EXPRESSIONS:

  • 分度器(ぶんどき)で測(はか)る: to measure with a protractor
  • 分度器(ぶんどき)を使(つか)う: to use a protractor
  • 分度器(ぶんどき)を当(あ)てる: to place a protractor (against something)

RELATED GEOMETRY TOOLS:

  • 定規(じょうぎ): ruler
  • 三角(さんかく)定規(じょうぎ): set square / triangle ruler
  • コンパス: compass (for drawing circles)
  • 直定規(ちょくじょうぎ): straightedge

USAGE CONTEXT:
Introduced in Japanese elementary school math (算数(さんすう)) when students learn about angles. Part of the standard 文房具(ぶんぼうぐ) (stationery) set for geometry.

Related Words

Related: コンパス (compass)
general
Added 2026.1.16 17:17 · Revised 2026.1.27 8:37
05500/05596_bundoki