overcivil
/ˌoʊvərˈsɪvɪl/Definitions
1. adjective
excessively polite or courteous to the point of insincerity
“The overly civil receptionist was seen as insincere by many guests.”
2. noun
a quality of being excessively polite or courteous
“The overcivil atmosphere in the meeting made it difficult to discuss serious issues.”