unofficially

adv.

without official authorization

同义词：on the side

not in an official capacity

"unofficially, he serves as the treasurer"

Unofficially
UNOFFICIALLY
(Unofficially) Enacting the Commons
Upgrading to Lollipop (unofficially)
Unofficially the gateway or router for a subnet is assigned the first
Unofficially Official: The U.S. Rebalance to Asia-Pacific and the U.S.-Japan-Taiwan alliance
The Exploitation and Utilization of the Unofficially Published Document Resources
Place Attachment in the Urban Unofficially Sacred Sites: A Case Study of the MT Youth House Church in Guangzhou
Are Patients in the Transition World Paying Unofficially to Stay Longer in Hospital? Some Evidence from Kazakhstan
‘Error 53’ fury mounts as Apple's software update threatens to kill iPhones that were repaired unofficially