noun, noun or participle which takes 'suru'
whispering; murmuring; talking in a low voice
Refers to speaking quietly, often to avoid being overheard or to convey intimacy. Can be used as a noun or with する.
隣の席の人が低語していて、内容が気になった。
The person at the next seat was whispering, and I wondered what they were talking about.
図書館では低語で話してください。
Please speak in a low voice in the library.