imheadhón Definitions (by source) Show all Aibidil Gaoidheilge & Caiticiosma: Seaán Ó Cearnaigh's Irish primer of religion, published in 1571 ‘centre’ 33.9 Aibidil Gaoidheilge & Caiticiosma: Seaán Ó Cearnaigh's Irish primer of religion, published in 1571. Editor: Brian Ó Cuív.