Seiji
given name · Latin script
Meaning: ‘Admonishing second [son]’; ‘pure second [son]’
A male name· listed as male by the registers that count names by sex
(measured from records)Officially recorded in 17 countries · latest register: SSA, 2025
/ʃeʒi/(machine-generated) Portuguese · model-generated
Seiji is a male given name written in the Latin script, with more bearers in the United States than in any other country.
- KNSt. Kitts & Nevis1 in 3.2Kas Sage(measured from records)
- FRFrance≈1 in 17Kas Sage
- GBUnited Kingdom≈1 in 18Kas Sage
carrying the name, as counted by its national register where one exists and as Mondonomo estimates it elsewhere (marked ≈ and "est." on hover). Where a country counts another spelling of the name rather than Seiji itself, the figure is that spelling’s, and it is named. One hue, darker where it is more common; hover a country for its figure.
- United States (measured from records)
- 2 (measured from records)
- Record sources
- 390 (measured from records)
- 1 in 3.2K (inferred from the name graph)
11,207 named Sage, 2010
recorded for this name
corpus datasets behind its best-documented spelling
strongest: highest-authority source
St. Kitts & Nevis, as Sage
measured from records inferred from the name graph
Spellings & scripts
(measured from records)Locally spelled Sage in US United States, GB United Kingdom, CA Canada and 3 more.
Spellings marked ● are how people bearing the name write it in our records, and ○ marks a model's transliteration; click a spelling to open its page.
Meaning & origin
(measured from records)‘Admonishing second [son]’; ‘pure second [son]’.
Cited for this meaning 1
- A concise dictionary of first names
Attested across 2 languages in the etymology graph.
Where in the world
(measured from records)Seiji counted together with the spellings and other-language forms grouped with it. Where a register counted another spelling, the row names it.
Sorted by bearers: national registers' counts, and Mondonomo's estimates (≈, est.) where no register counts.
| Country | Most common spelling | Sources | |||
|---|---|---|---|---|---|
| US United States | 11,207as Sage | 1 in 30K | 19K | Sage | 390 |
| FR France | ≈4,100 est. | ≈1 in 17K | 377 | — | 6 |
| GB United Kingdom | ≈3,900 est. | ≈1 in 18K | 3 | Sage | 181 |
| CA Canada | ≈1,800 est. | ≈1 in 23K | 26 | Sage | 135 |
| ZA South Africa | ≈1,200 est. | ≈1 in 52K | — | Sage | 28 |
| IE Ireland | ≈280 est. | ≈1 in 19K | — | Sage | 37 |
| NZ New Zealand | ≈270 est. | ≈1 in 20K | 30 | Sage | 44 |
| KN St. Kitts & Nevis | 17as Sage | 1 in 3.2K | 17 | — | 6 |
11,207 people counted by Census Bureau — Surname Frequency 2010, 2010. Exact figures are national registers' own counts, while figures marked ≈ and est. are Mondonomo’s estimates, counted from our sources and calibrated against those registers; hover one for how far to trust it in that country. A dash means neither exists.
Registers cited: Census Bureau — Surname Frequency 2010; Census Bureau — First Name Frequency 2020 by sex; NISRA — Baby names Northern Ireland full list (1997–present); Alberta Open Government — Frequency and Ranking of Baby Names by Year and Gender; INSEE — Fichier des noms de famille (1891–2000); DIA — Baby name popularity (1900–present); St Kitts & Nevis — Register of Electors 2026. Figures without a register are Mondonomo estimates; see Methodology.
Country figures for a list of names, at full precision, are available under licence rather than by scraping this table (how that works).
Notable people with this name
(measured from records)- Seiji Hisamatsub. 1912JPfilm director (1912-1990)
- Seiji Miyaguchib. 1913JPJapanese Actor (1913-1985)
- Seiji Ogawab. 1934JPJapanese biophysicist
- Seiji Ozawab. 1935JPJapanese orchestra conductor (1935–2024)
- Seiji Yokoyamab. 1935JPJapanese musician (1935–2017)
- Seiji Maeharab. 1962JPJapanese politician
- Kameda Seijib. 1964JPJapanese music producer, lyricist, composer, arranger, bassist (1964-)
- Seiji Mizushimab. 1966JPJapanese anime director
- Seiji Kiharab. 1970JPJapanese politician
- Seiji Kishib. 2000JPJapanese director of anime
The ten people covered by the most Wikipedia language editions — a proxy for cross-cultural notability, which favours historical and Western figures over equally prominent contemporary ones — shown by birth year. Source: Wikidata (CC0).
How to address them
(machine-generated)A formal English salutation is built on the surname, so it needs a full name — on its own, a first name only supports the informal form.
Evidence
(measured from records)29 registers and reference works attest this spelling, across 17 countries.
| Country | Register | Year | Count | Rank |
|---|---|---|---|---|
| US United States | Census Bureau — First Name Frequency 2020 by sex | 2020 | 612 | #17,586 |
| US United States | SSA — National Baby Names (1880–present) | 2007 | 19 | — |
| US United States | SSA — National Baby Names (1880–present) | 2011 | 16 | — |
| US United States | SSA — National Baby Names (1880–present) | 2012 | 15 | — |
| US United States | SSA — National Baby Names (1880–present) | 2006 | 14 | — |
| US United States | SSA — National Baby Names (1880–present) | 2008 | 13 | — |
| US United States | SSA — National Baby Names (1880–present) | 2005 | 13 | — |
| US United States | SSA — National Baby Names (1880–present) | 1995 | 13 | — |
| US United States | Census Bureau — First Name Frequency 2020 by sex | 2020 | 12 | #17,586 |
| US United States | SSA — National Baby Names (1880–present) | 2017 | 12 | — |
| US United States | SSA — National Baby Names (1880–present) | 2014 | 12 | — |
| US United States | SSA — National Baby Names (1880–present) | 2010 | 12 | — |
Reference works 3
- Dictionary of American Family Names
- Wikipedia given-name tokens
- Wikidata name items (native-script + romanized given/family names)
These works list the name; their figures are licensed and are not reproduced here.
Register rows as of the 2026-10-09 data build.
Frequently asked questions
- What does the name Seiji mean, and where does it come from?
- ‘Admonishing second [son]’; ‘pure second [son]’. Recorded by A concise dictionary of first names.
- How do you pronounce Seiji?
- In Portuguese /ʃeʒi/. Transcriptions are machine-generated except where a dictionary is named.
- Is Seiji a male or female name?
- Seiji is a male name. National registers that list it by sex list it as male: United States (Census Bureau, 2020) and Brazil (Brasil.IO genero-nomes (IBGE Censo 2010 mirror, CC-BY-SA)).
- In which country does Seiji have the most bearers?
- In the United States, the national register counted about 11 thousand people named Sage, more than in any other country we hold.
- Where is Seiji most common?
- No national register we hold counts the spelling Seiji itself. The densest figure for its family of spellings is St. Kitts & Nevis's: the national register counts about 1 in 3.2 thousand people named Sage.
- How common is the name Seiji?
- In the United States, the national register counted 11,207 people named Sage in 2010, about 1 in 30 thousand residents.
What do you want to know about Seiji?
Nobody replies to these one by one, but what readers ask decides what these pages answer next.
Query this name via API
curl -H "X-API-Key: YOUR_KEY" https://api.mondonomo.ai/api/v1/name-graph/seijiThe payload this page is built from: spellings and scripts, countries and languages, related names, and the registers that attest the form. It takes a free API key (1,000 requests a day), which returns what this page shows everyone; the full country table, every register citation and the year-by-year series come with a licensed key, as does bulk access.
About this data
measured from records inferred from the name graph machine-generated
These figures come from the data snapshot of and will change as it is rebuilt.
Statistics are aggregated from the Mondonomo name corpus; related names and etymology are inferred from the name graph; pronunciation and any machine-marked transliterations are model-generated. Read how the numbers are made, including their known failure modes, and where the data comes from.
Reference works we consult — surname dictionaries, official name registers, Wikidata and Wiktionary — are named directly, beside the claims they support. The per-country source counts also include datasets of person records: we publish how many there are and their authority tier, but not their names.
Cite this page Mondonomo, “Seiji”. Data snapshot 2026-10-13.