עֲנוֹ֙ וְאָ֣מְרִ֔ין לִנְבוּכַדְנֶצַּ֖ר מַלְכָּ֑א מַלְכָּ֖א לְעָלְמִ֥ין חֱיִֽי׃
זײ האָבן זיך אָפּגערופֿן און געזאָגט צו דעם מלך נבֿוכַדנֶצַר: אײביק לעבן זאָל דער מלך!
Rashi
They spoke up and said Aram. עֲנוֹ, they shouted. Every [expression of] עֲנִיָה in Scriptures is an expression of raising the voice.
Ibn Ezra
[Daniel 3:9] They spoke up (עֲנוֹ - ʿano): This is the customary practice (mishpat) for those speaking to the king: to offer a prayer that his days may be long (l'hitpallel she-ya'arichu yamav).