noun, noun or participle which takes 'suru', intransitive verb
secret meeting; clandestine meeting
A meeting held in secret, often with a nuance of secrecy for romantic, political, or conspiratorial reasons. Can be used as a noun or with する to mean 'to meet secretly'.
二人は週末に密会を重ねていた。
The two had repeated secret meetings on weekends.
彼
They met secretly to avoid being seen.