1911 Encyclopædia Britannica/Allah

ALLAH, the Arabic name used by Moslems of all nationalities for the one true God. It is compounded of al, the definite article, and ilah, meaning a god. The same word is found in Hebrew and Aramaic as well as in ancient Arabic (Sabaean). The meaning of the root from which it is derived is very doubtful; cf. Lane’s Arabic-English Lexicon, p. 82, and the Oxford Hebrew and English Lexicon, pp. 61 ff.