a combining form that enters into compounds denoting a unit one-quintillionth (10 −18) the size of the unit named by the stem.
denoting 10–18: attotesla, a
word-forming element meaning “one quintillionth,” 1962, from Danish atten “eighteen” (a quintillion is 10 to the 18th power), related to Old English eahtatene (see eighteen).
One quintillionth (10-18): attometer.
noun a high-power laser capable of producing pulses with a duration measured in attoseconds
attoparsec unit, humour About 31 mm (one inch). “atto-” is the standard SI prefix for multiplication by 10^-18. A parsec (parallax-second) is 3.26 light-years; an attoparsec is thus 3.26 * 10^-18 light years. Thus, one attoparsec per microfortnight is about one inch per second. This unit is reported to be in use (though probably not […]
noun the physics of structures and artefacts with dimensions in the attometre range or of devices, such as lasers, capable of producing pulses with a duration measured in attoseconds
to acknowledge the relation of a tenant to a new landlord. to turn over to another; transfer. verb (intransitive) (law) to acknowledge a new owner of land as one’s landlord (feudal history) to transfer allegiance or do homage to a new lord v. late 13c., Anglo-French, “to turn over to another,” from Old French atorner […]