Brussels, bubble, buckle, bustle, chuckle, couple, cudgel, double, funnel, hovel, huddle, hustle, knuckle, Lovell, muddle, muffled, muscle, muzzle, nuptial, puddle, puzzle, rubble, ruffle, Russel, Russell, Russell's, rustle, scuffle, shovel, shuffle, shuttle, smuggle, squirrel, struggle, stubble, subtile, subtle, supple, trouble, tunnel

disgruntled, rebuttal, redoubled, referral, unruffled, untroubled