1.
reading aloud; reading out
The act of reading text out loud, such as reading names from a list, reciting results, or reading a document aloud to an audience.
2.
text-to-speech; audio playback of text
A technology function in which a device or application converts written text into spoken audio. Common in accessibility features and language learning tools.
Usage
The noun form of the verb 読み上げる (to read aloud). Used both as a noun (読み上げ) and in verb form. In technology contexts, 読み上げ機能 (text-to-speech function) is extremely common.