I think it means "God is gracious", and is a Gaelic variation of Shona.
Irish Gaelic.
Scottish: Oidhche Shamhna shona dhut. Irish: Oíche Shamhna shona dhuit.
Irish Gaelic: Nollaig shona dhuit! (or dhaoibh, pl.) Scots Gaelic: Nollaig Chridheil
Nollaig chridheil in Scots Gaelic Nollaig shona in Irish Gaelic and Nollag Ghennal in Manx
Irish Gaelic: Breithlá shona dhuit. Scots Gaelic: Manx Gaelic: Welsh: Breton: Cornish:
25ú Breithlá shona, a Éanna. or Breithlá cuig bliain is fiche shona, a Éanna.
The Shona is a tribe that is part of the BAntu clan of southern Africa that speaks a Nguni language. Shona people are situated mainly in Zimbabwe with a few inhabitants in South Africa and Zambia.
Nollag shona (merry Christmas) pronounced; Nul-ag hun-aNollag shona duit (merry Christmas to you) duit pronounced; DitNollaig Shona Dhuit"Happy Christmas."
Nollaig shona agus Síocháin Chríost leat (singular) Nollaig shona agus Síocháin Chríost libh (plural)
In Scottish Gaelic Merry Christmas is Nollaig chridheilPronounced "nollik chree-hel"
Irish Gaelic would normally be "Nollaig shona dhuit!"(merry Christmas to-you).