Modern rhymes with:
postmodern, ultramodern, postmodern, ultramodern, bloedorn, hagedorn, heidorn, postmodern, premodern, ultramodern
Modern sounds like:
madron, mandarin, mandarine, mandarino, matern, materna, mathern, matherne, matrimony, matron, mattern, mediterranean, medrano, midterm, minturn, mitrano, moderne, mondrian, montrone, motoren, motrin, mottern, mottram