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nano

1 American  
[nan-oh, ney-noh] / ˈnæn oʊ, ˈneɪ noʊ /

noun

  1. Informal. nanotechnology.


nano- 2 American  
especially before a vowel, nanno-;
  1. a combining form with the meaning “very small, minute,” used in the formation of compound words (nanoplankton ); in the names of units of measure it has the specific sense “one billionth” (10-9 ).

    nanomole; nanosecond.


nano- British  

combining form

  1.  n.  denoting 10 –9

    nanosecond

  2. indicating extreme smallness

    nanoplankton

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

nano– Scientific  
  1. A prefix that means:

  2. Very small or at a microscopic level, as in nanotube. In this sense, this prefix is sometimes spelled nanno–, as in nannoplankton.

  3. One billionth, as in nanosecond, one billionth of a second.


nano- Cultural  
  1. A prefix meaning one billionth.


Usage

What does nano- mean? Nano- is a combining form used like a prefix meaning “very small, minute.” In names of units of measure, it means "one billionth." It is often used in scientific and technical terms. Nano- comes from Greek nânos or nánnos, meaning “dwarf.”What are variants of nano-?In some rare instances, nano- is spelled with a double -n-, becoming nanno-, as in nannofossil. When combined with words or word elements that begin with a vowel, nano- becomes nan-, as in nanoid. Want to know more? Read our Words That Use nan- article.

Etymology

Origin of nano1

By shortening

Origin of nano-2

Combining form representing Greek nânos, nánnos dwarf

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

After the iPod, there was an iPod mini, an iPod nano and an iPod shuffle.

From The Wall Street Journal • Mar. 6, 2026

Wie, a professor of organic and nano engineering at Hanyang University in South Korea.

From The Wall Street Journal • Nov. 1, 2025

His lab has other "BEAR" robots performing different tasks -- like the nano BEAR, which studies the way materials behave at the molecular scale using a technology called atomic force microscopy.

From Science Daily • May 21, 2024

"The inclusion of ultra-fine nano additives significantly enhances the material by increasing density and compactness."

From Science Daily • May 15, 2024

As Max piloted the Vonnegut down to the surface, I prepared for the possibility of combat by charging up my armor and buffing my avatar with several potions and nano packs.

From "Ready Player One: A Novel" by Ernest Cline