Grunden rhymes with:
dundon, london, lunden, munden, new-london, port-london, sundin, abandon, branden, brandon, brendan, brenden, brendon, chittenden, clarendon, condon, crittenden, denden, dundon, escandon, fessenden, glandon, guindon, harnden, herndon, kundun, landen, landon, linden, lindon, london, lunden, lynden, lyndon, mcalinden, mcclendon, mclendon, mclinden, mendan, minden, morandan, munden, nederlanden, new-london, port-london, rondon, rwandan, saindon, sanden, standen, strinden, sundin, tandon, tendon, ugandan, vanden, vanderlinden, vanderzanden, windon, wolfenden, zbinden
Grunden sounds like:
germantown, germination, grandin, grandma, grandon, grantham, grondin, grundman