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Boy

Guillermo

Guillermo is a boy's name meaning "Spanish form of William", drawing on Spanish roots. It peaked back in the 1990s and has been gradually easing since. In the current registry, it is a name plenty of people share. 1998 was this name's high-water mark in the U.S. birth records.

SpanishSpanish form of William
EtymologyMeaning "resolute protector"
Births by decade
1900s
44
1910s
253
1920s
821
1930s
783
1940s
941
1950s
1,495
1960s
2,113
1970s
3,360
1980s
4,383
1990s
6,490
2000s
6,095
2010s
2,976
Peaked in the 1990s · 29,754 total U.S. births since 1900