Named after anime artist, director, and producer Ichirô Itano, and primarily comes from the anime franchise Macross
. Itano created an attack where a ridiculously large number of missiles are launched from one fighter jet or robot at a target or targets, regardless of tactical necessity.
It is also characterized by the missiles' twisting, turning and crisscrossing contrails.
That jet just itano circus'd and totally missed...but it still looked pretty awesome.