militate [ˈmɪlɪˌteɪt] v.t., usually followed by "against" or "with"
1.) To have force or influence; bring about an effect or a change (The American Heritage Dictionary of the English Language).
Etymology: Latin militare, militat-, to serve as a soldier, from miles, milit- soldier.
"Oh, Mr. Lydgate, you know well what your advantages are. You know that our young men here cannot cope with you. Where you frequent a house it may militate very much against a girl's making a desirable settlement in life, and prevent her from accepting offers even if they are made" (Middlemarch, George Eliot, 1874).