Meaning

1 senses
  1. (Commonwealth, Ireland, UK, idiomatic, plural, plural only)A long time, years and years.

Origin

1876 or earlier. Possibly chosen because donkeys can be long-lived animals. Likely directl

1876 or earlier. Possibly chosen because donkeys can be long-lived animals. Likely directly related to donkey's ears, a less frequently used rhyming slang term for years.https://wordhistories.net/2016/06/30/donkeys-years/

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donkey's years — meaning, examples, forms, synonyms | Krumeto