imbricated (en)

arranged (scales, sepals, plates, etc.) so that they overlap like roof tiles

internecine (en)

(adjective) marked by slaughter; deadly / (adjective) mutually destructive / (adjective) of, relating to, or involving conflict within a group

officious (en)

(adjective) kind obliging / (adjective) dutiful / (adjective) volunteering one's services where they are neither asked nor needed; meddlesome / (adjective) informal unofficial