



The Latin Iesus is an irregular form of the 4th declension. (The Latin declensions are like verb conjugations in Spanish, but applied to nouns).

Iesus is in the singular nominative case: the "name" of the word (as seek it in the dictionary) and the form it takes when is grammatical nucleus of subject. Iesum is in singular acusative (like direct complement). And Iesu is the form that takes all another cases (dative, genitive and ablative singular and plural).

Since the formation of the Spanish language until the mid-20th century all Spanish speakers say the Latin name of Jesus Christ weekly in a ceremony: Mass. Consider the following passages of Mass in Latin:

Grátia Dómini nostri Iesu Christi, et cáritas Dei, et communicátio Sancti Spíritus sit cum ómnibus vobis.

...exspectántes beátam spem et advéntum Salvatóris nostri Iesu Christi.

Dómine Iesu Christe, qui dixísti Apóstolis tuis...

In the simplified version of the Roman Missal of St. Pius V in 1570 I count 3 mentions of Iesu and none of Iesus or Iesum. In a full version of modern Latin Mass I count 10 mentions of Iesu, 5 Iesum and none of Iesus. (It's an approach, the text changes daily).

Consequently, we can say that there is not really a loss of -s sound in the Spanish word "Jesús". What we have is a Latin cultism that led to the synthesis of two words in one. Iesu Christi became Jesucristo.

Until the eighteenth century remains the original orthographic form with two words separated by a space, by example this Spanish book titles:

But in the late eighteenth century there is evidence that the words are coming together in one compound word. A hyphen shows the first step of this join:

In 1790, an edition of a book prefers to use the hyphen, and 27 years later, the new edition of 1817 already uses the modern form (and has even lost the H):

Then we could say that the current Spanish form Jesucristo is used since circa 1800. A good evidence of this transition is found in this book

in which among the hundreds of references to Jesuchristo, appear hidden 3 times Jesu-Christo with an hyphen.

  • This is exactly the type of answer I'm looking for! I wonder if you can add some sources, especially for the second to last paragraph, about the origin of the two Spanish words. – Flimzy Aug 9 '15 at 18:29
  • Exactly. In medieval periods it was most common to see Jesus' name spelt jheſu. I'm currently transcribing a book from 1495 and it exclusively uses that spelling (jheſsu chriſtu in full, with a space) – user0721090601 Aug 10 '15 at 12:52
  • @guifa, sorry, what means "with a sieve" in your comment? – Rodrigo Aug 10 '15 at 22:01
  • @Rodrigo "with a space", stupid autocorrect on my phone (and no editing of comments) – user0721090601 Aug 10 '15 at 22:22



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  • @Flimzy: In spoken Spanish, even if not written, such a change occurs extremely frequently, and is well-documented in the literature as well. – Aprendedor Aug 10 '15 at 21:48

He encontrado una referencia en la Enciclopedia Católica Online que menciona al libro "Origin of the Name of Jesus Christ", Maas, Anthony. The Catholic Encyclopedia. Vol. 8. New York: Robert Appleton Company, 1910. http://www.newadvent.org/cathen/08374x.htm.

Esta referencia incide en el hecho de que "Jesús" era un nombre común en la época y que "Cristo" era una denominación, por lo que "Jesucristo" es resultado de su uso conjunto.

La palabra Jesus es la forma latina del griego Iesous, que a su vez es la transliteración del hebreo Jeshua, o Joshua, o también Jehoshua, que significa “Yahveh es salvación”. (...) El nombre griego está relacionado con el verbo iasthai, sanar; (...) Si bien en el tiempo de Cristo el nombre Jesús parece haber sido bastante común le fue impuesto a Nuestro Señor por orden expresa de Dios (Lc. 1,31; Mt. 1,21), como señal de que el Niño estaba destinado a “salvar a su pueblo de sus pecados.”

La palabra Christ, Christos, equivalente griego para la palabra hebrea Messias, significa “ungido”

Sólo luego de la Resurrección el título se convirtió gradualmente en nombre propio, y la expresión Jesucristo o Cristo Jesús se convirtió en una sola designación. (...)

El uso del artículo definido antes de la palabra Cristo y su gradual desarrollo hacia un nombre propio muestra que los cristianos identificaban al portador de ese nombre con el Mesías prometido de los judíos.

La caída de la s forma parte del proceso histórico de la evolución de las palabras a través de su uso. Sin embargo, no puedo encontrar una regla general que la explique con mayor detalle.



  • Christ means Messiah, not king.






Besides this makes it alot easier to say too! =)


The term "Cristo Jesús" does occur in several places in the Bible. For example, in Efesios 2:10.


I think this follows the word order chosen in the original Greek. The English translations do the same thing. Paul sometimes uses one word order, sometimes the other.

As to why "Jesús Cristo" becomes "Jesucristo", I concur with the repsonders who theorize that it rolls off the tongue easier, and that's why it evolved that way.


Most likely it is a mix of Spanish and Greek.


