What Is In Excelsis Deo?

What Is In Excelsis Deo? noun. the hymn beginning, in Latin, Gloria in Excelsis Deo, “Glory in the highest to God,” and in the English version, “Glory be to God on high.” Also called great doxology, greater doxology. What does Excelsis mean in English? : in the highest degree. What is in Excelsis Deo mean?