Welsh word Nadolig comes from Latin nascor, Proto-Italic *gnātos, and later Latin natus (Son (of plants) growth, growing. Son, birth, age, years.)
| Dictionary entry | Language | Definition |
|---|---|---|
| nascor | Latin (lat) | I am a number of years old. I am born, begotten. I arise, proceed. I grow, spring forth. |
| *gnātos | Proto-Italic (itc-pro) | |
| natus | Latin (lat) | Son (of plants) growth, growing. Son, birth, age, years. |
| natalis | Latin (lat) | Anniversary. Birthday Natal (of one's birth). |
| natalicius | Latin (lat) | Birth, birthday (attributive). |
| natolic | Old Welsh (owl) | |
| Nadolig | Welsh (cym) | Christmas. |