What is "o'hagan"

O'Hagan is an Irish surname originally from the pre 10th century Old Gaelic Ó hÁgáin, meaning perhaps "Little Flamboyant Fire from the Sun", being derived from Aodh the pagan sun god and Og meaning young, they are the "male descendant of Aodh" the pagan sun god, a personal name meaning "fire". Aodh was a pagan god worshipped by the early natives. The very first recorded O'Hagan was a descendant of King Owen, and was a district justice of the peace