IPA: /səbˈviːn/
KK: /səbˈviːn/
To come or occur in a way that provides assistance or support.
The new policy will subvene the efforts of the community to improve local education.
Past: subvened
Past Participle: subvened
Subvene is formed from "sub-" (meaning under) and "venire" (meaning to come). The word describes the act of coming to aid or support from a lower position.
Think of something 'coming' ('venire') 'under' ('sub-') to provide help — that's why subvene means to come to someone's aid.