Surname Macgillycuddy (Macgillycuddy 
) , in all the world, is a very rare last name. The family name Macgillycuddy is habitual in Uruguay, where it is a rare surname, Ireland, and New Zealand. Measured by absolute frequency, the name is most common in Australia, Uruguay, and Ireland.
| VARIANT | COUNTRY |
|---|---|
| Macgillycuddy | Australia, New Zealand, Ireland, United Kingdom, Uruguay |