The Symbol of The Rose
Denotes confidentiality since ancient times.
The story tells of Aphrodite who gave a rose to her son Eros. He, in return, gave it to the god of silence - Harpocrates to keep Aphrodite's indiscretions private. Roses painted the ceilings of ancient Roman banquet rooms, hung in council meetings and private chambers, and decorated the confessionals in Christian churches. Through time, being under the rose ("sub rosa") has always meant that the conversation you're part of is absolutely secret.