the ring-fort of Mic Corra; the ring-fort of the sons of Corr?
Mic Corra (gen. Mhac gCorra) — plural patronymic or surname

The evidence for this anglicised place-name is somewhat problematic.

Most early historical forms of the name have a penultimate -o- or -u- such as ‘Rahmagorra’ (Cen.), ‘Ramagorra’ (HMR) and ‘Rathnagura’ (Rentals: Wood-Martin), which are at odds with John O’Donovan’s suggested ‘Rath Mhac Garraigh, “Magarry’s fort”’ in the Ordnance Survey Parish Namebook. It is true that a number of the earlier historical forms with penultimate -a- such as ‘Rathfagarry’ (BSD) and ‘Rathfagary’ (Hib. Del.) could be considered to support derivation from the likes of *Ráth Mhac Garraigh, but these are found in related sources and therefore somewhat problematic. Saliently, however, the local Irish pronunciation noted in pencil during the course of the Ordnance Survey, ‘raith mhac gurraigh’, would also be at odds with suggested *Mhac Garraigh. On the whole, the linguistic evidence does not reflect a low front vowel such as /a/ in the penultimate syllable of the underlying Irish name, but rather a higher back-vowel such as /o/ which was subsequently fronted to /u/ in anglicisation, as seen in Rathmagurry.

Derivation from Ráth Mhic Fhearaigh “the fort of Mac Fhearaigh (McGarry)” was also considered, given the prevalence of that surname in Sligo (see Sloinnte Gaedheal is Gall, p.359), but this was rejected for much the same reason as O’Donovan’s suggested ‘Rath Mhac Garraigh’. (This surname appears to be found in bf Sessuegarry/Seiseadh Mhic Fhearaigh “the sixth (measure of land) of Mac Fhearaigh (anglic. McGarry)” (#45653), another townland in the parish of Achonry, although the evidence there is not without its problems.)

In any case, given the unsuitability of Rathmagurry from *Mac Garraigh, *Mac Fhearaigh or similar, the most likely derivation is from Ráth Mhac gCorra or similar, containing a plural form of a patronymic or surname based on the personal name Corr (gen. Corra) which is attested in early Irish sources (see CGH p.568).

No rath is recorded in the townland; the first element may refer to the ringfort just over the townland boundary in Drumbaun (par. Achonry).
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