The Crucifix

What does the acronym INRI (could also be written as JNRJ) at the top of the crucifix stand for?

I’esus Nazarenus Rex I’udaeorum   which translated in English is
Jesus of Nazareth (the Nazarene) King of the Jews.

Since Latin uses the alphabet I instead of J, the J in “Jesus” and “of the Jews” is written as “I”.

John alone mentions that the title on the Cross was in three languages.

The Synoptic Gospels mention the title (with slight differences) but not that it was in three languages.