Resolute protector
A rare spelling variant of Guillermo, which is the Spanish form of William. It is derived from the Germanic elements 'wil' (will or desire) and 'helm' (helmet or protection).
Less common today
Gillermo isn't in the latest US Top 1000. It last peaked at #3,173 in 1993.
US births per 5-year period, 1990–present (SSA data).
