Spelunking rhymes with:
flunking, plunking, debunking, flunking, junking, plunking, banking, blanking, blinking, clanking, cranking, debunking, drinking, flanking, flunking, franking, honking, junking, linking, nanking, nonbanking, outflanking, planking, plinking, plunking, ranking, reinking, rethinking, shrinking, sinking, spanking, stinking, tanking, thanking, thinking, unthinking, winking, yanking