Recognised Surname Variations
The Gaelic forms of the surname derived from the original forms of the personal names Flandbrat and Flandgal found in the earliest manuscripts, and were commonly written in accordance with either the traditional (pre-1948) or reformed spelling conventions as follows:-
| Ó Flannabra | Ó Flanngaile | Ó Flannaoile |
| Ó Flanaoile | Ó Flannghaile | Ó Flannabhra |
In some remote rural areas, there are rare instances of Phonetic variations of the Gaelic forms. These records are only found in Irish-speaking communities and fall mid-way between the Gaelic form and the Anglicised form since they preserve the sound of the Gaelic surname in the midst of either English or Latin text. Variations from the sixteenth century fiants to the nineteenth century parish registers include the following:-
| O Flanura | Flanura | Flanure |
| Flanarough | O Flanor | Flannra |
| O'Flanuragh | O'Flanneragh | Flannra |
The Anglicised forms are susceptible to as many spelling variations as the wit of man may devise. It is important to bear in mind that the stardardisation of surnames only commenced in the early nineteenth century with the introduction of the national schools system. The following variations have been compiled from the Tithe Applotment Books (1824 - 1838), Griffith's Primary Valuation (1848 - 1864), the Irish civil registration records for births, marriages and deaths in the period 1845 - 1935, and verifications from the Y-DNA Project :-
| Flanary | Flanery | Flannery |
| Flannary | Flannerry | Flanelly |
| Flannelly | Flanley | Flanaly |
| Flannaly | Flanarough | Flanry |
| Flanerry | Flannarry | Farrenery |
| Flannely | Flannerly | Flamery |
| Flanherey | Flaneley | Flanelle |
| Flanell | Flaner | Flanhery |
| Flannarry | Flannealley | Flannelley |
| Flanneny | Flannory | Flennery |
| Flenley |
There is an established principle in law called the Rule of Idem Sonans. This means that in order to establish legal proof of relationship from documentary evidence, it is not necessary for the name to be spelt absolutely accurately if, as spelt, it conveys to the ear, when pronounced in the accepted ways, a sound practically identical to the correctly spelt name as properly pronounced. Simply put, names that sound similar are deemed to be equivalent.
It is important to remember that all of the spelling variations are equally valid, and it would be ludicrous to suggest that someone currently named Flannery is "more of a Flannery" than, for example, someone currently named Flanary.
