For example, McDowell, or McDonald, or McKenna, etc. Is it necessary to capitalize that letter following "Mc"? And if yes, why is this so?

  • 1
    Related: Etymology for Mc and O' in names
    – RegDwigнt
    Jun 10 '11 at 23:00
  • The same goes for "De" and "Di" in Italian and "de" in Hispanic surnames: the following letter is capitalized. (Though, from what I've seen, there is a mandatory space after "de" in Hispanic names, and an optional space after "De" or "Di" in Italian names.) Jun 11 '11 at 4:05
  • I've come across the name Maconochie. I know nothing about it, except that it seems to be a Scottish surname, and that it's apparently never spelt MacOnochie.
    – user25910
    Sep 10 '12 at 18:20
  • 1
    The general rule in English is you spell people's names exactly how they tell you to spell them, whether or not that seems consistent with any pattern you've ever seen.
    – zwol
    Jun 30 '16 at 1:55

As Etymology for Mc and O' in names says, Mc is an abbreviation for Mac, and Mac is a Gaelic term meaning "son of". Hence the name McKenna means "son of Kenna", and since Kenna is a proper name, it is capitalized, even when combined with Mac.

(Of course "mac" alone is itself not a proper name, and from one view wouldn't need to be capitalized. However since it is taken as beginning the whole surname, it is capitalized as the initial letter of a proper name. In this respect, it is treated like English most often treats other borrowed prepositions in names, such as de from French and van from Dutch.)

  • 2
    Strangely enough, it's rare to see the Norman Fitz- treated this way: It's Fitzroy, Fitzclarence, Fitzsimmons.
    – Uticensis
    Jun 11 '11 at 0:27
  • 11
    Correction: "Mac" just means "son". The "of" comes from changing the nominative Diarmaid into genitive Diarmada (and then Anglicizing the heck out of it to get McDermot or something).
    – Marthaª
    Jun 11 '11 at 0:29
  • 7
    Or, for McKenna: the starting name was probably something like Cináed or Cionaodh, which becomes Cionaodha in the genitive, and then the English get ahold of it and it becomes unrecognizable. (But eminently more pronounceable.)
    – Marthaª
    Jun 11 '11 at 0:39
  • Re: Fitz - It being a mark of (acknowledged) bastardy might have a little something to do with the diminution of the father's name.
    – bye
    Oct 1 '14 at 18:38
  • When writing in Gaelic (Irish), girls' names are written with Nic or Úi instead of Mc or O as they mean "daughter" instead of "son". So that, technically, daughters and sons have slightly different surnames. The English version of the name uses Mc/Mac for everybody though. Dec 16 '15 at 10:01

It depends in part on where the person comes from. In Scottish names, the second capital is almost always correct - McDonald, MacDonald, etc (but note that 'Machinery' does need a capital H).

In names of Irish descent, sometimes the owners insist on no second capital; I had a colleague whose surname was Macdonald and he was not happy when the 'd' was capitalized. I'm not sure how general that is.

  • 2
    McDonald, MacDonald, and Macdonald are all separate Scottish surnames.
    – TRiG
    Oct 5 '11 at 16:54
  • Right. It has nothing to do with Eireland -- "Macdonald" is just a separate name.
    – Fattie
    Aug 1 '14 at 15:03

Some Scottish surnames do not have a capital. Some can be spelt with capital and some without. I was told by a Macintyre, that his name if spelt with the small case i, it meant that historically they were of the lower orders, but the name MacIntyre, with capial I, meant they were of the professional, or I guess landed classes. That's what he told me anyway.

  • 4
    (That sounds very dubious, just FWIW! folk etymology, sort of thing...)
    – Fattie
    Aug 1 '14 at 15:03
  • 1
    I haven't heard that before, but as a Macfarlane I'm disinclined to believe it... Aug 18 '15 at 0:41

Not the answer you're looking for? Browse other questions tagged or ask your own question.