Sisu

/S-IH-S-AH/

Unisex ChristianAtheist Finnish origin ScandinavianEuropean

Grit and inner resolve, from the Finnish sisu, an almost untranslatable cultural ideal of stoic determination and courage that endures long past the point others give up. Regarded as a defining Finnish virtue, the word names a quiet, stubborn strength of will, and as a name it confers that prized tenacity.

See Sisu scored for your family

Meaning & origin

Sisu is a unisex's name of Finnish origin, traditionally used in Christian families. The name means "Grit and inner resolve, from the Finnish sisu, an almost untranslatable cultural ideal of stoic determination and courage that endures long past the point others give up. Regarded as a defining Finnish virtue, the word names a quiet, stubborn strength of will, and as a name it confers that prized tenacity." and belongs to the Courage cluster — names for children who will grow into bold, fearless hearts.

Beyond its Christian heritage, Sisu is also used in Atheist traditions, reflecting how this name has traveled across cultures.

Common among Scandinavian, European families, Sisu carries cultural weight that goes beyond its dictionary definition — it's a name with a story and a community.

Numerology of Sisu

Numerology assigns each name a single-digit destiny number by summing its letter values. Different schools use different mappings — NameRoot computes both so you can see how Sisu resonates in either tradition.

Pythagorean
5
freedom and adventurous change
Chaldean
4
stability and disciplined work

How Sisu sounds

NameRoot scores the phonetic fit of every name against the sound of your last name. The pronunciation of Sisu breaks down into 4 phonemes: /S-IH-S-AH/. In the app, you'll see how those sounds flow with your family name across rhythm, stress, and consonant clusters.

The six signals, applied to Sisu

NameRoot scores every name across six independent dimensions. Here's how Sisu maps to each — install the app to see the full compatibility score for your specific family.

01 — Birth Star
Nakshatra match
Enter your baby's birth date in the app and we'll compute the nakshatra compatibility score.
02 — Numerology
Destiny alignment
Pythagorean and Chaldean life-path calculations (destiny 5) matched against your family's own numerology profile.
03 — Phonetics
Last-name fit
Rhythm, stress, and consonant clusters measured with IPA to see how Sisu flows with your family name.
04 — Meaning
Courage
Sisu belongs to the Courage cluster — names for children who will grow into bold, fearless hearts.
05 — Cultural & Tradition
Christian
As a Christian name, Sisu carries religious and cultural weight scored against your family's heritage — plus grandparent-name matches, saint's-day alignment, and generational naming patterns scored against your family tree.
06 — Uniqueness
Popularity balance
How common Sisu is today versus historically — finding the sweet spot between familiar and forgotten.

Names similar to Sisu

If Sisu resonates with you, these names live in the same world — drawn from the same tradition, sharing the same meaning, or echoing a similar sound.

From the same tradition

Other Christian unisex names, common in Scandinavian families

Luca
Light-giving, the Italian form that crosses gender boundaries with effortless Mediterranean grace — Luca is Luke softened by Italian vowels into a name equally at home on a son or a daughter. It carries the warmth of southern European sunshine, the artistic heritage of a culture that elevated beauty to a moral principle, and the international ease of a name that needs no translation
Riley
A major American cross-gender favorite with very strong current household normalization
Nico
Victory of the people, compressed into a name as quick and bright as a struck match — Nico is the pan-European short form of Nicholas and Nicole, carrying the Greek concept of popular triumph in two vivid syllables. It sounds at home in Rome, Amsterdam, and Buenos Aires, a name that belongs to no single country because it belongs to the spirit of celebration itself
Skylar
From Dutch 'Schuyler' (scholar, shelter). American adaptation. Used for all genders since 1990s

Sharing the same meaning

Other Christian unisex names from the Courage cluster

Alexis
Defender, protector, the one who wards off harm — Alexis comes from the Greek verb meaning to defend and has moved between genders across centuries and continents. It carries the guardian's vigilance, the instinct to step between danger and the vulnerable, and the ancient Greek conviction that the highest use of strength is not conquest but protection of those who cannot protect themselves
Nikita
Victorious one — Nikita (Russian Никита, from Greek Nikētēs 'victor') shares its root with Nike and Nikolai. In Russian and Slavic usage it is a masculine name, though Western adoption has often treated it as feminine. The earliest Saint Nikita was an early Christian martyr remembered for his steadfastness.
Finley
Fair warrior, the white-haired hero of Gaelic legend — Finley descends from the same root as Fionn mac Cumhaill, the legendary hunter-warrior of Irish and Scottish mythology. It carries the pale radiance of northern skies, the martial spirit of Highland culture, and the modern versatility of a name that moved from the clan chieftain's hall to the nursery without losing any of its Celtic fire

Names that sound similar

Christian unisex names that open with the same syllables as Sisu

Sequoia
The giant tree, named for the Cherokee scholar who gave his people a written language — Sequoyah created the Cherokee syllabary in the 1820s, the only known instance of a single person independently inventing a complete writing system
Siru
Small fragment or flake, from the Finnish siru, a tiny piece or speck. As a feminine name it carries an affectionate sense of something small and precious, in keeping with a Finnish habit of choosing short, plain nature-words that feel intimate and tender rather than grand.
Sinag
Ray of light, sunbeam — Sinag (Tagalog) is the Filipino word for ray of light, particularly a sunbeam piercing through clouds. The Philippines' tropical sunlight is iconic to Filipino landscape photography and the rays of the eight-rayed sun on the Philippine flag.

Common questions about Sisu

What does the name Sisu mean?

Sisu means "Grit and inner resolve, from the Finnish sisu, an almost untranslatable cultural ideal of stoic determination and courage that endures long past the point others give up. Regarded as a defining Finnish virtue, the word names a quiet, stubborn strength of will, and as a name it confers that prized tenacity.." It is a unisex name of Finnish origin, traditionally used in Christian families.

Is Sisu a boy or girl name?

Sisu is a unisex name, used for any gender.

What is the origin of the name Sisu?

Sisu is of Finnish origin, used in Christian, Atheist traditions, commonly among Scandinavian, European families.

What is the numerology of Sisu?

Sisu has a Pythagorean destiny number of 5 — freedom and adventurous change.

See how Sisu scores for your family

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