child's play, frippery, nonproblem, nothing, picayune, shuck(s), small beer, small change, trifle, triviality

naught(also nought), nothingness, smoke, zeropeanuts, pittance, song, straw, two bitsbunk, claptrap, drivel, folly, fribble, fudge, hogwash, humbug, humbuggery, nonsense, piffle, rot, trash, triviabit, crumb, dab, dram, lick, mite, ounce, particle, pinhead, scintilla, shred, smidgen(also smidgeon or smidgin or smidge), soupçon, speck, spot, tad, touch, trace