longest

long +‎ -est

• (Received Pronunciation) IPA^(key): /ˈlɒŋɡəst/, /ˈlɒŋɡɪst/
• (General American) IPA^(key): /ˈlɔŋɡəst/

• Audio (US):

  (file)

• (cot–caught merger) IPA^(key): /ˈlɑŋ.ɡəst/
• Rhymes: -ɒŋɡəst, -ɒŋɡɪst (Received Pronunciation); -ɔŋɡəst (General American); -ɑŋɡəst (cot–caught merger)

longest

1. superlative form of long: most long
   • 2025 October 1, Chris Howe, “Top 10: Britain's most significant rail bridges: Ribblehead Viaduct”, in RAIL, number 1045, page 57:

     It's not the longest or tallest viaduct in Britain, but the landscape upon which it sits makes for a stunning backdrop.

longest

1. superlative form of long: most long

longest

1. (archaic) second-person singular simple present indicative of long

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