| Name |
Pronunciation |
Meaning |
English Spelling |
Gender |
| Gadra, Gadhra | (GEER-a) | | Geary, Gary | M |
| Gáeth, Gaoth | (GAY) | "clever, wise" | | M |
| Gáethíne, Gaothín | (ge-HEEN) | dim. of Gáeth | | M |
| Gaimredán, Gaimhreadhán | (guv-RAWN) | "wintry person" | | M |
| Gallchobar, Gallchobhar | (GAL-chor) | | Gallagher | M |
| Garalt, Gearalt | (GAR-alt) | | | M |
| Garb, Garbh | (GARV) | "rough" | | M/F |
| Garbán, Garbhán | (GOR-vawn) | | Garbháin, Garvin | M |
| Gébennach, Géibheannach | (GEYV-an-ach, GEYN-ach) | "captive, prisoner" | Geaney | M |
| Gelgéis, Geiléis | (gel-AYSE) | "bright swan" | | F |
| Geróit, Gearóid | (GAR-od) | from Old German Gairovald, ger "spear" vald "rule" | Gareth, Garret | M |
| Gerróc, Gearróc | (GAR-owg) | from gerr "short" | Garrick | M |
| Gilla Bréannain, Giolla Bhréannain | (GUL-a VREY-nin) | "servant of St Brendan" | | M |
| Gilla Brigde, Giolla Bhrighdhe, Giolla Bhríde | (GUL-a VREED-a) | "servant of St Brigid" | | F |
| Gilla Cellaig, Giolla Cheallaigh | (GUL-a CHAL-a) | "servant of St Cellach" | | M |
| Gilla Cáemgein, Giolla Chaoimhín | (GUL-a CHEEV-een) | "servant of St Kevin" | | M |
| Gilla Comgaill, Giolla Chomhghaill | (GUL-a CHOL) | "servant of St Comgall" | | M |
| Gilla Críst, Giolla Chríost | (GUL-a KREEST) | "servant of Christ" | Gilchrist | M |
| Gilla Epscoip, Giolla Easpaig | (GUL-a AS-pig) | "servant of the bishop" | Gillespie | M |
| Gilla Ísu, Giolla Íosa | (GUL-a EE-sa) | "servant of Jesus" | Gileese | M |
| Gilla Mochutu, Giolla Mochuda | (GUL-a mu-CHUT-a) | | "servant of St Mochutu" | M |
| Gilla na Náem, Giolla na Naomh | (GUL-a na NEYV) | "servant of the saints" | | M |
| Gilla Pátraic, Giolla Phádraig | (GUL-a FAWD-rik) | "servant of St Patrick" | | M |
| Gillucán, Gillagán | (GUL-a-gawn) | "little lad" | Gilligan | M |
| Glaisne | (GLAS-nee) | dim. of Glass | | M |
| Glass, Glas | (GLOS) | "green, grey, grey-blue" | | M |
| Glassán, Glasán | (glos-AWN) | dim. of Glass | | M |
| Gobbán, Gobán | (gub-AWN) | from goba, "a smith" | | M |
| Gobnat, Gobnait | (GUB-nit) | fem. form of Gobbán | | F |
| Goffraid, Gofraidh, Gofraí | (GUF-ree) | borrowing of Old German Godafrid guda "god" frithu "peace" | | M |
| Gormán | (GOR-mawn) | dark, swarthy complexion | Gorman | M/F |
| Gormgilla, Gormghiolla | (GURM-yi-la) | gorm "green, grey" gilla "lad" | | M |
| Gormlaith | (GURM-la) | gorm "illustrious, splendid" flaith "sovereignty" | | F |
| Gráinne | (GRAW-ney) | | | F |
| Grella, Grealla | (GRAL-a) | | | F |
| Grellán, Greallán | (GREL-awn) | | | M |
| Grian | (GREE-an) | "sun-goddess" | | F |
| Guaire | (GWAR-ee) | "noble, proud" | | M |
| Gúasacht | (GWAS-acht) | "danger, peril" | | M |
| Guss, Gus | (GUS) | "force, vigour, fierceness" | | M |
| Gussán, Gusán | (GUS-awn) | dim. of Guss | | M |