Submitted by György Chityil ... on Fri, 01/19/2018 - 22:28 Hierarchy: PrefixDescription: In the International System of Units and other metric systems of units, multiplying the unit to which it is attached by 10<sup>?24</sup>. Symbol: yNgram: yocto-Ngram Text: yocto-Source: WiktionaryIssue: 0Ngram Count: 1