backdoor
adjective [ before noun ] disapproving uk/ˈbæk.dɔːr/ us/ˈbæk.dɔːr/
后门的;私下的，秘密的;不诚实的
relating to something that is done secretly or in a way that is not direct or honest
The change was immediately dismissed as a backdoor tax increase. 这一改动被认为是变相增税而立刻遭到否决。