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1. Get involved, so as to alter or hinder an action, or through force or threat of force
   "Why did the U.S. not intervene earlier in WW II?";
   - step in, interfere, interpose
    
2. Be placed or located between other things or extend between spaces and events
   "This interlude intervenes between the two movements"; "Eight days intervened"
    
3. Occur between other event or between certain points of time
   "the war intervened between the birth of her two children"

Derived forms: intervened, intervenes, intervening

Type of: come about, fall out, go on, hap [archaic], happen, interact, lie, occur, pass, pass off, take place

Encyclopedia: Intervene