Guillerma

Girls' name

Will + helmet, through Guillermo

Guillerma has been given to 33 babies in the U.S. since 1922. It was used fewer than 5 times in 2025, so it doesn't appear in the latest year's list — today it's a genuinely uncommon pick. Its peak year was 1930, with 7 recorded.

Babies named Guillerma, 1940

1 in 461,000

Guillerma over time, 1880–2025

Girls

Based on births in the U.S. Babies given the name each year. Hover the chart — or focus it and use the arrow keys — for any year. Gaps mean the name was given fewer than 5 times that year; these counts are unpublished.

Guillerma: meaning, origin, and history

Will + helmet, through Guillermo

Deeper origin not confirmed in the cited records

What Guillerma means

Guillerma belongs to the name family reached through Guillerma → Guillermo → William → William. Its meaning is “will + helmet”.

Origin, language, and formation

Guillerma is used in Spanish.

Related names and everyday forms

Related names include Guillermo and William.

Pronunciation and spelling

In Spanish, Guillerma is pronounced /ɡiˈʝeɾma/.

American usage and historical context

In the United States, 33 girls were recorded with the name Guillerma between 1922 and 1940. Its highest annual count was 7 in 1930; its best national rank was #3,812 in 1930.

Sources & methodologyReferences, data & attribution

Meaning, origin, and language notes draw on the references below.

American popularity figures use published Social Security Administration records for this exact spelling. Counts below five for a name, sex, and year are omitted.

Wiktionary material is available under CC BY-SA 4.0.

How common is Guillerma?

Guillerma had fewer than 5 recorded uses in 2025, so these figures use 1940, the last year it was published.

Among all babies, 1940: 1 in 461,000; 5 of 2,302,666 births
Among girls only: 1 in 229,000; <0.01% of girls
Rank, 1940: Unranked; Fewer than 5 uses
Coin-flip room size: 319,218 kids; Even odds of a second one

Where Guillerma sits on the popularity scale

Rarest published (5 a year)#1 — Olivia (13,544)

Chance at least one other child shares the name

If the other children were drawn at random from the 1940 national name distribution. Real classrooms cluster by region and community, so treat these as a floor, not a ceiling.

Class of 20Under 1%

Class of 30Under 1%

Grade of 100Under 1%

School of 500Under 1%

Put another way: gather 319,218 children born in 1940 and it's an even bet that one of them is another Guillerma. In a class of 30 the chance is Under 1%.

When Guillermas were born

Half of everyone ever recorded as Guillerma was born before 1927 — so the typical Guillerma is around 98 today.

Median birth year: 1927; About 98 years old
Biggest decade: 1920s; 63.6% of all use
Born in the last 25 years: 100.0%; A modern name
Recorded since 1950: 0; People you could plausibly meet

Choose a decade

1920s — 63.6% of all recorded uses (21).

Is Guillerma rising or falling?

Rank movement and count movement can disagree — the number of distinct names in use keeps growing, so a name holding a steady count still slides down the list. Both are shown.

Rank vs 1 year ago: —; Not ranked then
Rank vs 5 years ago: New entry; Not ranked then
Rank vs 10 years ago: —; Not ranked then
Births vs 10 years ago: —; Not published both years
Share of its own peak: 0%; Peak was 1930 (7)
Years since peak: 95; Years
Year-to-year steadiness: Very steady; 0% average annual change
Best rank ever: #3,812; 1930

Spellings of Guillerma

Guillerma is not the most common spelling — Guillermina is, with 98.3% against Guillerma's 1.7%.

Guillermina98.3%1,925
Guillerma1.7%33

Grouped by closeness of spelling (up to two letter changes), same sex, with a floor on all-time use. It catches Sophia/Sofia and Aiden/Ayden, and misses spellings that sound alike but look different, like Sean and Shawn.

Where Guillerma is used

Across 1910–2025, Guillerma was most concentrated in Texas — about 1 in — girls, against 1 in 2,046,820 across all states with data.

00 per 100,000

State popularity map

Most concentrated

1Texas1 in —

Shading is the share of that state's recorded girls given this name, not the raw count — otherwise the map would just show which states are biggest. Unshaded states have no published records for this period. U.S. birth records suppress state-year counts below 5; state counts therefore don't add up to the national total. Every state links to its full rankings. Guillerma has too little recent state data to map, so this covers all years from 1910.

Guillerma by the numbers

The raw record for each sex the name is used for.

As a girl's name

Rank in 2025: Unranked
Trend vs 5 yrs ago: —
Best rank ever: #3,812; 1930
Peak year: 1930; 7 that year
First recorded: 1922
Last recorded: 1940
All-time count: 33
Count in 2025: Under 5

Names similar to Guillerma

Matched on shared beginnings and endings, similar length, and comparable popularity.

Guinivere Guillermo Guinnevere Guilliana Guilianna Guisselle Guilda Guiselle Guiliana Guinette Guisela Guisell Guinevere Guinda Guisel Thurma Guila Parma Guida Kerma Therma Eurma Lorma Kharma

Sibling names for Guillerma

Names from the same era and popularity tier — the two things that make a sibling set feel deliberate — skipping lookalike spellings and shared initials.

For a sister

Billy Donald Ardith Roma Marvel Bobby Socorro Josefina

For a brother

Carrol Normand Mary Frances Dudley Delmar Sanford Jules

Explore around Guillerma

Top names of 1930, Guillerma's peak year The 1930s in full Other names that peaked in 1930 Girls' names starting with G