While names can have multiple spellings that are pronounced the same, the most widely used and the most traditional way to spell this name is "G-l-a-d-y-s".
Meaning & History
From the old Welsh name Gwladus, possibly derived from gwlad "country". It has historically been used as a Welsh form of CLAUDIA. This name became popular outside of Wales after it was used in Ouida's novel 'Puck' (1870). - BehindTheName.com
Name spellings weren't standardized several generations ago, so many people spelled even their own name in a variety of ways.
There are so many wonderful ways to make a baby name unique for your baby girl or boy. If you are looking for a unique way to personalize the name you've selected, consider an alternate spelling for the name. Whether it's Leigh instead of Lee or Anya instead of Anna, using a unique spelling can give a special twist to a unique name.
Check out tips on how to create baby names with clever spellings at SheKnows.com.