Definition of rampageous in US English:

rampageous

adjective

  • Boisterously or violently uncontrollable.

    ‘a rampageous backwoodsman’
    • ‘There's something about a rampageous woman flashing men that resonates with power.’
    unruly, unmanageable, disorderly, undisciplined, uncontrollable, unrestrained, rowdy, uncontrolled, disruptive, truculent, difficult, refractory, rebellious, mutinous, out of hand, riotous, out of control, wild, turbulent, uproarious, tumultuous, tempestuous, unbridled, irrepressible, boisterous, roisterous, rackety
    View synonyms

Origin

Early 19th century from rampage + -ous.

Pronunciation

rampageous

/ˌræmˈpeɪdʒəs//ˌramˈpājəs/