Undeg

Undeg is formed from the Welsh numerals 'un' (one) and 'deg' (ten), which together give the word for eleven in the traditional Welsh counting system. Welsh has a vigesimal (base-twenty) counting system alongside a decimal system, and 'un deg un' (one ten one) is used in the modern decimal form for eleven. The word 'undeg' itself can function as a compound numeral root.

The use of numerals as personal names is found in several cultures, typically indicating birth order in a family. In Welsh tradition, as in Roman tradition with names such as Quintus or Decimus, the numeral name recorded something significant about the child's position in a family lineage. A child named Undeg may have been the eleventh born, or the name may have carried a more symbolic significance relating to the number.

The element 'deg' also carries the sense of ten, and in Welsh 'deg' on its own can mean fair or handsome as a poetic adjective in certain dialectal or archaic contexts, which may have contributed to the appeal of this numeral name as a given name beyond simple birth-order recording.

Numeral names in Welsh reflect the importance of family structure and birth order in traditional Welsh society, where large families were common and distinguishing between many children required creative naming strategies. Such names preserve a record of demographic and social history within the language itself.

While uncommon in the modern era, names like Undeg speak to the extraordinary flexibility and creativity of Welsh naming practices, which drew on mythology, nature, geography, virtues, and even mathematics for inspiration. Reviving a name like Undeg today is a statement of deep engagement with the Welsh language as a living creative system rather than merely a repository of familiar names.