longevity

• longævity (archaic)

Early 17th century, learned borrowing from Latin longaevitās, from longaevus (“ancient, aged”) +‎ -itās. The first part is related with English long and this association led to the alternative pronunciation with /ŋ/.

• (UK) IPA^(key): /lɒnˈd͡ʒɛv.ɪ.ti/, /lɒŋ-/

  • Audio (Southern England); /lɒnˈd͡ʒɛv.ɪ.ti/:

    (file)

  • Audio (Southern England); /lɒŋˈd͡ʒɛv.ɪ.ti/:

    (file)

• (US, Canada) IPA^(key): /lɑnˈd͡ʒɛv.ə.ti/, /lɔn-/, /lɔŋ-/, [ɫɑ̃nˈd͡ʒɛv.ə.ɾi], [ɫɔ̃n-], [ɫɔ̃ŋ-]
• (General Australian) IPA^(key): /lɔŋˈd͡ʒev.ə.ti/, [lɔŋˈd͡ʒev.ə.ɾi]

longevity (countable and uncountable, plural longevities)

1. The quality of being long-lasting, especially of life.

   Grandpa had incredible longevity: he lived to be 105 years old!

   • 2020 July 1, David Allen, “Signalling from Leeds along the S&C”, in Rail, page 74:

     This 142-year-old tiny ex-LNWR SB [signal box, at Batley] is an amazing survivor, probably owing its longevity to its location alongside a level crossing. Indeed it started life as a gate box with the delightful name of Lady Ann's Crossing.

2. Duration over time; persistence.
   • 2018, James Lambert, “Anglo-Indian slang in dictionaries on historical principles”, in World Englishes, volume 37, page 255:

     A ‘postdating’ is an example of the use of a lexical item at a later date than currently recorded and these are important in establishing the longevity of use of a term and whether or not it has become obsolete.

• permanence

• longevous

• “longevity”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.