Mid 18th century; earliest use found in Jonathan Swift (1667–1745), writer and dean of St Patrick's Cathedral, Dublin. From Irish pocán small male goat from poc male goat + -án, suffix forming diminutives.
Definition of puckaun in US English:
puckaun
nounpʌkˈɔːn
Irish English
A billy goat.
Origin
Mid 18th century; earliest use found in Jonathan Swift (1667–1745), writer and dean of St Patrick's Cathedral, Dublin. From Irish pocán small male goat from poc male goat + -án, suffix forming diminutives.