Since you did not specify which Gaelic, here are two answers
Nollaig Chridheil is Scottish
Irish would be Nollaig faoi shéan agus faoi shonas duit!
"Nollaig cridheil agus bliadhna mhath ùr"
Nollaig chridheil agus Bliadhna mhath ùr!
Nollaig Chridheil
Irish Gaelic: Breithlá shona dhuit. Scots Gaelic: Manx Gaelic: Welsh: Breton: Cornish:
Gleann Sonais, Gleann Séin or Gleann Gliondair in Irish; in Scots Gaelic: ?
maol
càirdean
seanair
ogha
Muir (sea)
Camshron
tapadh leat
glasraichean
buadhaich air
Taigh gràis ?