Guillermino
This is a Spanish variation of the Old High German "Willehelm," which means "resolute protector."
Alternates:
Giermo, Gigermo, Gijermo, Gillermo, Gillirmo, Giyermo, Guermillo, Guiermo, Guilermón, Guillelmo, Guillermo, Guirmo, Gullermo, Quillermo
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