rebellious adj.

c. 1300, "resisting an established or rightful government or law, insurrectionist; lawless," from Old French rebelle "stubborn, obstinate, rebellious" (12c.) and directly from Latin rebellis "insurgent, rebellious," from rebellare "to rebel, revolt," from re- "opposite, against," or perhaps "again" (see re-) + bellare "wage war," from bellum "war" (see bellicose). By 1680s as "belonging to or controlled by rebels."

word-forming element making adjectives from nouns, meaning "having, full of, having to do with, doing, inclined to," from Old French -ous, -eux, from Latin -osus (compare -ose (1)). In chemistry, "having a lower valence than forms expressed in -ic."