atto-


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atto-

pref.
One quintillionth (10-18): attotesla.

[From Danish or Norwegian atten, eighteen, from Old Norse āttjān; see oktō(u) in Indo-European roots.]

atto-

prefix
denoting 10–18: attotesla. Symbol: a
[from Norwegian, Danish atten eighteen]

atto-

a combining form denoting one-quintillionth (10−18) the size of the unit denoted by the second element of the compound: attosecond.
[< Dan or Norwegian att(en) eighteen + -o-]

atto-

A prefix meaning a quintillionth (10-18). For example, 1 attometer = 1 quintillionth of a meter.