Sub-rosa and Unlicensed

Sub-rosa adjective - Designed and carried out secretly or confidentially.

Unlicensed and sub-rosa are semantically related. In some cases you can use "Unlicensed" instead an adjective phrase "Sub-rosa".

Unlicensed adjective - Lacking official approval.

Sub-rosa and unlicensed are semantically related. Sometimes you can replace phrase "Sub-rosa" with "Unlicensed", this terms are similar.