1.VerbTo arrive, usually without warning or invitation.
To make an attack or incursion, from or as if from a vantage ground; to come suddenly and with violence.
To arrive suddenly or unexpectedly, especially in a manner that causes disruption or inconvenience.
"My neighbour descended upon me just as I was walking out the door."
2.VerbTo make an attack or incursion, from or as if from a vantage ground; to come suddenly and with violence.
3.VerbTo arrive suddenly or unexpectedly, especially in a manner that causes disruption or inconvenience.
"My neighbour descended upon me just as I was walking out the door."
4.VerbTo visit in large numbers, especially a public place.