Akademik

exa-

Prefix used in the SI and metric system to signify a multiple of one quintillion (10¹⁸).

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[Gr. hexa because it is sixth in the series of prefixes for multiples] a combining form used in naming units of measurement to indicate a quantity one quintillion (10¹⁸) times the unit designated by the root with which it is combined. Symbol E.

Medical dictionary. 2011.