The Collaborative International Dictionary
Subvening
Subvene \Sub*vene"\, v. i. [imp. & p. p. Subvened; p. pr. & vb. n. Subvening.] [Pref. sub- + L. venire to come. See Subvention.] To come under, as a support or stay; to happen.
A future state must needs subvene to prevent the whole
edifice from falling into ruin.
--Bp.
Warburton.
Wiktionary
subvening
vb. (present participle of subvene English)