Synonyms for Invade (same or very similar meaning)
WordNet sense 1 (occupy in large numbers or live on a host):
infest, overrun, overrun
WordNet sense 2 (to intrude upon, infringe, encroach on, violate):
intrude on, encroach upon, obtrude upon
WordNet sense 3 (march aggressively into another's territory by military force for the purposes of conquest and occupation):
occupy
From the ODE community, based on WordNet
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