fastest

fast +‎ -est

fastest

1. superlative form of fast: most fast

   He set a new fastest time for running a mile.

   • 2018, VOA Learning English > China's Melting Glacier Brings Visitors, Adds to Climate Concerns

     Scientists say it is one of the world’s fastest-melting glaciers.

fastest

1. superlative form of fast (adverb): most fast

fastest

1. (archaic) second-person singular simple present form of fast

   But thou, when thou fastest, anoint thine head, and wash thy face.

• Fassett, setfast

• IPA^(key): /ˈfastəst/
• Hyphenation: fas‧test
• Homophone: fasstest

fastest

1. Second-person singular present of fasten.
2. Second-person singular subjunctive I of fasten.

• IPA^(key): /ˈfaːstəst/
• Hyphenation: fas‧test

fastest

1. Second-person singular preterite of fasen.
2. Second-person singular subjunctive II of fasen.