The database can be browsed alphabetically. There are four sorting keys (options) provided:

  1. Bare form: The nominative case form of the surname minus all prefixes, articles and initial mutations. This is a novel gender-neutral form developed for this project.
  2. Base form: The male form of the surname in the nominative case.
  3. Ordinary form: The ordinary form of the surname in the nominative case, be it the male, wife or daughter form.
  4. Root form: The personal name from which the surname is derived. We use this as a lexical title for each surname cluster.


Bare form Base form Ordinary form Root form
Male Briain Ó Briain Ó Briain Brian
Wife Briain Ó Briain Uí Bhriain Brian
Daughter Briain Ó Briain Ní Bhriain Brian

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