IPA: /səbˈvɜːsɪvnəs/
KK: /səbˈvɜrsɪvnəs/
The quality or state of trying to overthrow or undermine an established system or authority.
The subversiveness of the group's actions raised concerns among the authorities.
Subversiveness → It is formed from "sub-" (meaning under) and "vertere" (meaning to turn). The word describes the quality of turning something upside down or undermining established authority.
Think of 'turning' ('vertere') something 'under' ('sub-') — that's why subversiveness means the quality of undermining or challenging authority.