I.about [美 əˈbaʊt, 英 əˈbaʊt]副about often appears as the second element of certain verb structures in English (fool about, knock about, move about, etc). For translations, see the relevant verb entry (fool, knock, move, etc)
It was the first such barge-based test, a necessity that had come about because the powerful thermonuclear devices completely obliterated the small islands following detonation.