atto-

atto- — noun

1. a prefix used with scientific units of measurement to mean one quintillionth (10

1.名詞C2
釋義

a prefix used with scientific units of measurement to mean one quintillionth (10⁻¹⁸, or 0.000000000000000001) of the base unit — for instance, an attosecond is a quintillionth of a second and an attometer is a quintillionth of a meter.

例句

Physicists can now measure events that last just a few attoseconds using laser pulses.

a few attoseconds

The diameter of a proton is roughly one attometer, far too small for an ordinary microscope to see.

attometer, diameter

文法句型

atto- + [unit of measurement]

用法筆記

Almost exclusively used in physics, chemistry, and engineering contexts. The most common compounds are attosecond (time) and attometer (length).

常見錯誤

❌The experiment took five atto-seconds.
✅The experiment took five attoseconds.
💡When atto- is added to a unit, the result is a single compound word without a hyphen.
❌atto-metre
✅attometre
💡Metric prefixes combine directly with the unit name without a hyphen in standard scientific spelling.