millimeter

noun

mil·​li·​me·​ter ˈmi-lə-ˌmē-tər 

variants US millimeter or British millimetre

: a unit of length equal to 1/1000 meter see Metric System Table

Examples of millimeter in a Sentence

Recent Examples on the Web

As a marked return to high heels takes hold, one big push at Sam Edelman is the expansion of the brand’s best-selling Hazel pump, which is getting an update with a new a 105-millimeter heel. —Stephen Garner, Footwear News, 6 Feb. 2026

Yukon gold potatoes are shaved to a thickness of about a millimeter, layered with butter and a little corn starch and baked. —Sean Timberlake, Sacbee.com, 5 Feb. 2026

Steph is a lifelong painter who used to work on massive canvases (one of her pieces can be seen at the store), but now her masterpieces can be measured in millimeters. —Brock Keeling, Oc Register, 4 Feb. 2026

Another was 10 millimeters — a size when gastroenterologists start to truly worry because larger polyps are more likely to turn into something bad. —Gustavo Arellano, Los Angeles Times, 3 Feb. 2026

Word History

Etymology

French millimètre, from milli- + mètre meter

First Known Use

1797, in the meaning defined above

Rhymes for millimeter

• amphitheater
• centimeter
• centimetre
• decimeter
• ergometer
• expositor
• gasometer
• gravimeter
• hexameter
• manometer
• milliliter
• millimetre

Kids Definition

millimeter

noun

mil·​li·​me·​ter ˈmil-ə-ˌmēt-ər 

: a measure of length equal to ¹⁄₁₀₀₀ meter see metric system table

Medical Definition

millimeter

noun

mil·​li·​me·​ter

variants or chiefly British millimetre

ˈmil-ə-ˌmēt-ər 

: one thousandth of a meter

—abbreviation mm