Rebelliousness rhymes with:
seriousness, callousness, carelessness, cautiousness, consciousness, contagiousness, contentiousness, dangerousness, disingenuousness, fractiousness, graciousness, hellaciousness, helplessness, homelessness, hopelessness, joblessness, lawlessness, nervousness, outrageousness, pompousness, powerlessness, recklessness, restlessness, righteousness, ruthlessness, seriousness, surfaceness, weightlessness
Rebelliousness sounds like:
reflagging, replacing, repligen's, republican's, republicans, republicans', repulsing