1. intervene, step in, interfere, interpose, interact
usage: 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?"
2. intervene, lie
usage: be placed or located between other things or extend between spaces and events; "This interludes intervenes between the two movements"; "Eight days intervened"
3. intervene, happen, hap, go on, pass off, occur, pass, fall out, come about, take place
usage: occur between other event or between certain points of time; "the war intervened between the birth of her two children"
Adjective
1. intervening, middle (vs. late) (vs. early)
usage: occurring or falling between events or points in time; "so much had happened during the intervening years"