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.
Also nanno-; especially before a vowel, nan-.
Origin of nano-
combining form representing Greek nânos, nánnos dwarf
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for nano-
denoting 10 –9nanosecond Symbol: n
indicating extreme smallnessnanoplankton
Word Origin for nano-
from Latin nānus dwarf, from Greek nanos
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
Medicine definitions for nano-
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Science definitions for nano-
A prefix that means:
Very small or at a microscopic level, as in nanotube. In this sense, this prefix is sometimes spelled nanno-, as in nannoplankton.
One billionth, as in nanosecond, one billionth of a second.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.