ruler

/ˈɹuːlə(ɹ)/noun

A person who governs a country or holds power over others.

Example sentence

“The ancient kingdom was united under a single ruler.”

Handy that the measuring stick shares the word: both senses trace back to the idea of keeping things straight.

Related words

highlighterA pen with bright, transparent ink used to mark important parts of a text.eraserA small tool, usually made of rubber, used to rub out marks made with a pencil or pen.calculatorA machine, usually electronic, built to carry out mathematical calculations.pencilA writing tool with a thin graphite core, usually encased in wood and sharpened to a point.compassAn instrument with a magnetized needle or electronic sensor that shows which way north is.stationeryPaper, envelopes, pens, and other supplies used for writing and office work.