-ptiv adjective
: irrupting or tending to irrupt
irruptive forces
as
a. : rushing or bursting in or upon : entering forceably or violently
the irruptive roar of new engines — J.G.Cozzens
b. of an igneous rock : intrusive
c. : marked by irruption
the irruptive stage of rabbit increase
: undergoing irruption
the irruptive deer herds of the state
— compare cyclic
• ir·rup·tive·ly -tə̇vlē adverb