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definitions

Irish pennant

noun Nautical Slang: Sometimes Offensive.
  1. an unwhipped rope end.
  2. any strand or rope end left hanging untidily.

Origin of Irish pennant

First recorded in 1880–85

Usage note

Though no longer used as a deliberate slur, this term is sometimes perceived as insulting to or by the Irish. It originated in the Royal Navy in the 1800s, during the time of sailing ships.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018