In Irish it's "Ó hUaine"
ANOTHER ANSWER:
The following names are listed as Irish Gaelic versions of the surname Green(e) in Fr. Woulfe's book of Irish surnames:
de Graoin (of English origin) Limerick, Dublin, Waterford
Ó hUaithne/Ó hUainidhe of W. Cork
Ó hUaithnín of Mayo, Tipperary, Clare
Mac Glasáin/Mac Glaisín of Derry and Louth-Armagh-Monaghan-Fermanagh
Mac Giolla Ghlais of Donegal
Uaithne "some parts of Ireland"
Glas "some parts of Ireland"
Ó hUidhrín in parts of W. Mayo-W. Galway
Ó Fathaigh in some parts of Galway
Unlike English, the Gaelics have different words for green:
In Irish Gaelic:
uaine = vivid green, verdant
glas = green colour; grey colour
In Scottish Gaelic:
uaine = green
glas = grey-green
In Irish it's "de Grae"
Comment:
The Irish name Mac Giolla Riabhaigh is sometimes anglicised as 'Gray' mainly in Co. Longford.
Tá an talamh glas
green (the color)
The Irish (Gaelic) version is 'Croí Ró-Naofa'. Scottish Gaelic: ?
glas / uaine
Dear Green Place
Glas, pronounced like gloss. Also uaine.uaine green glas grey (green in certain uses)
In Irish it's "pláinéad glas"
blue, green grey comes from gaelic for glas
piosa beag de glas
Tá an léine sin go deas
In the Irish, spelled 'tulach', it means a low hill, hillock, mound'. In Scottish Gaelic it's also 'tulach' ( a small green hill).
Cnoic Glasa is the Irish. "Is glas iad na cnoic i bhfad uainn" (Far away hills are green, Irish proverb).Scottish Gaelic: ?
Irish Gaelic would say glas as in Féar glas(green grass) but uaine (vivid green, verdant) is used for green as in clothing, etc.Scottish Gaelic uses uaine but glas means "grey". Glas actually encompasses green and grey in Irish.Manx:Welsh uses glas, gwyrdd and ir.Breton:Cornish: