sub rosa

From Wiktionary

[change] Etymology

From the Latin word sub (meaning "under") + the ablative of rosa (meaning "rose"). Literally meaning "under a rose" or "under the rose".

[change] Adjective

Positive sub rosa

Comparative none

Superlative none

1. done in secret

   He made a sub rosa attempt to steal the cake.

[change] Adverb

Positive sub rosa

Comparative none

Superlative none

1. in secret

   He stole the cake sub rosa.