Bible Dictionaries
In Excelsis

1910 New Catholic Dictionary

(Latin: excellere, to raise up)

On high, the highest, occurring in the hymn of the angels to the shepherds at Our Lord's birth, meaning that God is eminently above all things, and perhaps alluding to the idolatrous altars, which occasionally the Jews themselves, and always the people about them, used to build on the "high places," the tops of hills.

Bibliography Information
Entry for 'In Excelsis'. 1910 New Catholic Dictionary. https://www.studylight.org/​dictionaries/​eng/​ncd/​i/in-excelsis.html. 1910.