For background on how the map was made (and its flaws), see the relevant blog entry.
|Keogan||Quite numerous: Meath-Cavan etc. Ir. Mac Eochagáin (SI); Ó Ceogáin (SGA) so that it may sometimes be a variant Cogan. Woulfe says it is a variant of Mag Eochagáin, i.e. Geoghegan, q.v.|
|Keoghan||Quite numerous: Waterford-Kilkenny, Midlands. Ir. Mac Eochagáin, dimin. of Eochaidh. Cognate with Keogan and Keohane.|
|Keohan||rare: Waterford. Ir. Mac Eocháin, see Keohane.|
|Keohane||numerous: mainly Cork. Ir. Mac Eocháin, dimin. of Eocha, a variant of Eochaidh, but in spoken language Ó Ceocháin. SI & SGG.|
|Ó Ceocháin||Keohane: líonmhar: Corcaigh thiar: claochlú ar Mac Eocháin, q.v.|
DEDs where Keoghan and a second surname are found together