Citron
A source of confusion is that "citron" or similar words in French (and other languages), and English are false friends, as they refer to the lemon. Indeed, into the 16th century, the English name "citron" included the lemon and perhaps the lime as well.
Kabbad
The Kabbad refers to a citron-like fruit or citrus hybrid which was first described in 1963 by the Moroccan professor Henri Chapot, in his article named ""Le Cédrat Kabbad et deux autres variétés de cédrat"", who remarked it to be a biological hybrid between the citron and the orange sourcing from Damaskus, Syria.
Following is from The Citrus Industry vol. 1 Chap.4: