This eBook describes many surname and christian name variations and peculiarities and may help you find that elusive Irish ancestor in birth, death and marriage records.
The 1869 Post Office Directory of Victoria Australia lists the names of post towns with their abbreviations and alternative names.
These town names and abbreviations are from the 1869 Post Office Directory of Victoria which you can read and search on Google Books.
A list of alternative Irish given names, for example Biddy is used for Bridget and Ned for Edward.
In searching for Irish ancestors remember that the Irish used a lot of shortened or alternative names for example Biddy for Bridget and Sally for Sarah.
Rootsireland has a good section on alternative first names.
This can be confusing. Below are some that I have come across:
Female christian names:
Abbey, Abigail, Deborah, Debby for Gobinet or Gobnait;
Anty or Anto for Anastatia;
Bessy, Betty, Beth for Elizabeth;
Biddy for Bridget; Cis for Cecelia;
Daisy for Mary;
Dot for Dorothy;
Fanny for Frances;
Judith for Johanna;
Kitty for Katharine;
May for Mary;
Minnie for Mary;
Mollie for Mary;
Nancy for ?;
Nanno for Honora;
Nellie for Ellen, Eleanor or Helen;
Nora for Hanora;
Peggy for Margaret;
Sally for Sarah;
Male Christain names:
Anto for Anthony;
Con and Connor for Cornelius;
Darby or Derby for Jeremiah
Edmund, Edward and Edmond are used for each other;
Ned for Edward.
This very old book “Varieties and Synonymes of Surnames and Christian Names in Ireland” by Robert E Matheson 1901 can be read online at Archive.org. The following pages deal with alternative christian names.