Sabian (n.)

an adherent of a religious sect mentioned thrice in the Qu'ran (in which they are classified with Christians and Jews as monotheistic "true believers" tolerated by Muslims), 1610s, from Arabic, but a word of uncertain origin. As an adjective from 1748.

Perhaps the reference in the word is to a Gnostic sect akin to the later Mandæans (if the word derives, as some linguists think it does, from Arabic ch'bae "to baptize," Aramaic tzebha "he dipped, dyed"); but it has the appearance of derivation from the Semitic root of Hebrew tzabha "host, army" (see Sabaoth), and as the Sabians were thought to have been star-worshippers, the word was interpreted as referring to the "host of heaven." Related: Sabaism "star-worship" (Century Dictionary says Sabeanism is incorrect).