McDermott Irish Surname: History, Origins & Heritage of a Connacht Royal Family

McDermott family crest mug on Irish tartan, celebrating McDermott Moylurg Roscommon royal heritage

McDermott is one of the great royal names of Connacht, the name of princes who never lost their title.

Where does the McDermott name come from?

McDermott is an anglicised form of the Gaelic Mac Diarmada, “son of Diarmaid” — a celebrated personal name meaning something like “free man” or “without envy,” borne by the legendary Diarmaid of the Fénian tales. The family descends from the royal line of Connacht.

The MacDermots of Moylurg

The MacDermots were Kings, later Princes, of Moylurg in County Roscommon, with their seat at the Rock of Lough Ké. The head of the family is still known as “The MacDermot, Prince of Coolavin,” one of the very few Gaelic chiefly titles recognised into modern times. As one of the historic royal names of Connacht, McDermott is found today across Ireland and among the diaspora in the United States, Canada, Australia and Britain.

McDermott family crest mug on Irish tartan, a McDermott heritage gift
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Did you know?

  • McDermott comes from the Gaelic Mac Diarmada.
  • Diarmaid means something like “free man” or “without envy.”
  • The MacDermots were Kings of Moylurg in Roscommon.
  • Their seat was the Rock of Lough Ké.
  • The head of the family is still “The MacDermot, Prince of Coolavin.”

Related Irish family names

You may also like McDonnell, McDowell, and Barry.

Carry the McDermott name with you

We craft heritage gifts for thousands of Irish and Scottish family names — mugs, woven blankets, ornaments and more. To find yours, type it into the search bar at the top of the page, or browse the McDermott collection here.

Frequently asked questions

Is McDermott an Irish surname?

Yes — McDermott is a Gaelic Irish surname, from Mac Diarmada, the royal MacDermots of Moylurg in Connacht.

What does McDermott mean?

It means “son of Diarmaid,” a name understood as “free man” or “without envy.”

Is there a McDermott family crest?

Families of the name have heraldic traditions; the crest and tartan artwork on our McDermott products is created as decorative heritage artwork to celebrate the name.

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