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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

In the second approach, the team employed nano imprinting, a process allowing for the printing of nanostructures using a mold.

From Science Daily • Mar. 28, 2024

The nano spiked surfaces were manufactured at the Melbourne Centre for Nanofabrication, starting with a smooth silicon wafer, which is bombarded with ions to strategically remove material.

From Science Daily • Mar. 26, 2024

“Glue. The nano kind. You can stick your shoes to the ceiling with this stuff and hang upside down.”

From "Uglies" by Scott Westerfeld