nano
nano — prefix
1. Added before a unit of measurement to mean one thousand millionth (10⁻⁹) of that
Added before a unit of measurement to mean one thousand millionth (10⁻⁹) of that unit — for example, a nanosecond is one billionth of a second.
A nanosecond equals one billionth of a second, far too fast for the human eye.
nano- + second creates nanosecond
The new processor can perform calculations in just a few nanoseconds.
Erik checked whether the gap between the two metal plates was within 10 nanometers of the target size.
The lab weighs each sample in nanograms to measure tiny amounts of a chemical compound.
- giga-
means one billion (10⁹), the opposite scale direction
文法句型
nano- + [unit of measurement]
用法筆記
This is an SI (International System of Units) prefix. It attaches directly to measurement words such as meter, second, gram, and liter without a hyphen in standard spelling. Although nano- is historically a combining form from Greek, it now functions as a productive SI prefix for any new measurement term.
常見錯誤
2. Added before nouns in science and technology to refer to things that are built,
Added before nouns in science and technology to refer to things that are built, measured, or operated at the scale of individual atoms and molecules.
Nanotechnology allows engineers to build tiny machines that work at the molecular level.
nano- + technology: engineering at molecular scale
Nanoparticles in this sunscreen block UV rays without leaving a white layer on the skin.
Kim's research team is testing nanomaterials that are both stronger and lighter than steel.
Dr. Okafor explained how nanorobots could one day deliver medicine directly to a cancer cell.
文法句型
nano- + [noun]
用法筆記
This sense is most common in compound words related to nanotechnology, materials science, and medicine. It implies working at a scale of 1-100 nanometers.
3. Used to form established scientific compound nouns where nano- attaches to a non
Used to form established scientific compound nouns where nano- attaches to a non-unit noun to describe something of nanometer-scale or billionth-scale size — for example, nanoplankton are tiny organisms that pass through normal filters.
Nanoplankton are so small that they pass through most standard filtering nets.
nano- + plankton: billionth-scale organisms
The geologist identified nanofossils in the sediment that date back millions of years.
Amira analyzed how nanostructures on a lotus leaf make water roll off the surface.
Noor's team is studying nanobubbles to see if they can improve wastewater treatment systems.
文法句型
nano- + [noun (non-unit)]
用法筆記
This reflects the older combining-form tradition from Greek, where nano- was attached to scientific nouns rather than SI units. Unlike the SI prefix (sense 1), this pattern is not productive for new terms — it occurs in already-established vocabulary such as nanoplankton, nanofossil, and nanostructure.