cearta : fourth
The Illunse word for fourth is cearta. In Irish cearta means rights (law). Cearta is a rare last name.
This word is a mixture of the Old English word for fourth féorða (fourth, as an ordinal) which I transliterate to feortha, and the Latin word for fourth quartus (fourth (in a series); 4th part), which I transliterate to cwuartus.
My previous Illunse word for fourth was ceurta. I tweaked this word because I changed the word for four.
Here's a link to fourth in J.R.R. Tolkien's words.
Sorry about all the number revisions, but on second look I'm seeing ways I'd rather construct these words.