Compos sui
“Master of oneself.”
Latin phrase
What does “Compos sui” mean?
Compos sui translates as “Master of oneself.”
Calm, self-controlled and in charge of your own mind.
“Compos sui” word by word
| Latin | English | Grammar |
|---|---|---|
| Compos | in possession of, master of | nominative singular masculine or feminine adjective (compos, genitive compotis), “having control of”; it takes a genitive of what is controlled |
| sui | of oneself | genitive singular of the reflexive pronoun sui, sibi, se; it refers back to the subject and has the same form for he, she, or it |
How to pronounce “Compos sui”
Both pronunciations sound the same here. Stress the first syllable of compos and the first syllable of sui, which is said as one beat, close to “SWEE” when spoken quickly.
The story behind it
Word for word the phrase says “in possession of oneself”. Compos is an adjective meaning having mastery or control of something, and it is followed by a genitive. Here the genitive is sui, “of oneself”, so the whole phrase describes someone who is fully in command of themselves.
Compos with a genitive is good classical Latin. The best-known example is compos mentis, “in possession of one’s mind”, which still survives in English and in law for a person of sound mind. Compos sui follows the same pattern, but the phrase compos sui as a fixed saying is less firmly tied to one author or text.
Today it is used as a short way to say self-possessed: calm under pressure, not ruled by temper, fear or impulse. It fits well with the Stoic ideal of self-mastery, though the phrase itself is not a known Stoic slogan.
How to use “Compos sui”
A compact choice for a tattoo, a ring engraving or a desk motto about self-discipline and a steady mind. It also works as a caption or a card for someone who stayed composed through a hard time.
- Latin
- Compos sui
- English
- Master of oneself.
- Source
- Latin phrase
- Era
- Antiquity
- Theme
- Self-control
Common mistakes
- Do not read it as “master of others”. Sui is reflexive and points back to the person themselves.
- Compos is the same for masculine and feminine, so you need not change it for a woman. For several people, the plural is compotes sui.
- Do not confuse it with compos mentis, which means “of sound mind” and is often a legal or medical phrase, not a motto about self-mastery.
- Compos sui is not a famous quotation from one named ancient author, so avoid crediting it to Seneca, Cicero or anyone else.
Questions about “Compos sui”
What does “Compos sui” mean literally?
Literally “in possession of oneself”, from compos (having control of) and sui (of oneself). In natural English it means master of oneself, or self-possessed.
Is “Compos sui” correct Latin for a tattoo?
Yes. Compos takes a genitive, and sui is the correct reflexive genitive, so the grammar is sound. It is short and clear, which makes it a safe choice for ink.
How do you pronounce “Compos sui”?
In Classical Latin it is roughly KOM-pos SOO-ee. The Church pronunciation is the same here, since no c or g comes before e or i.
What is the plural of “Compos sui”?
For several people use “compotes sui”, “masters of themselves”. Compos changes to compotes in the plural, while sui stays the same.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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