Derived from the Gaulish male name Draccios, or Latin Thracius ("of Thrace, Thracian"), and the well-identified Celtic suffix -āko ("place, property"), such Norman surnames themselves sprung from several Tracy place-names in France.
It may also be derived from the Irish word for three, with an association to the Tuatha Dé Danann.
The first reference to the surname in the Irish annals was in 1008: "Gussan, son of Ua Treassach, lord of Ui-Bairrche, died.
"[citation needed] According to historian C. Thomas Cairney, the O'Tracys were one of the chiefly families of the Uí Bairrche who were a tribe of the Erainn who were the second wave of Celts to settle in Ireland between about 500 and 100 BC.
[2] In England and Wales, the name Tracy was not unknown, but unusual, with about two a year, from 1837 until 1955, when, following the success of the American film star Spencer Tracy,[citation needed] the name quite suddenly became very popular, rising to a maximum of 7667 babies being given that name in 1964, but after 1970 the popularity quickly declined to 475 in 1985.