noun, noun or participle which takes 'suru', transitive verb
Rare literary word for whispering, especially into someone's ear. In modern Japanese, 囁き (ささやき) or 耳打ち (みみうち) are far more common.
古い小説で「耳語」という言葉を見つけた。
I came across the word 耳語 in an old novel.
He whispered into her ear.