"Notwithstanding, as a dog hath a day, so may I perchance have time to declare it in deeds." [Queen Elizabeth, 1550]
"It is ill wakyng of a sleapyng dogge." [Heywood, 1562]Phrase put on the dog "get dressed up" (1934) may refer back to the stiff stand-up shirt collars that in the 1890s were the height of male fashion (and were known as dog-collars at least from 1883), with reference to collars worn by dogs. The common Sp. word for "dog," perro, also is a mystery word of unknown origin, perhaps from Iberian.