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Definition of Irish twin
1. Noun. (slang) Either of a pair of siblings born nine to 12 months apart, especially if born within the same calendar year. ¹
¹ Source: wiktionary.com
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1. Noun. (slang) Either of a pair of siblings born nine to 12 months apart, especially if born within the same calendar year. ¹
¹ Source: wiktionary.com