1 syllable:
beds, breads, creds, deads, dreads, ed's, edds, fed's, feds, fred's, freds, head's, heads, keds, ned's, pthreads, redds, reds, reds', sheds, shreds, sleds, sledz, spreads, steads, steds, ted's, threads, treads

2 syllables:
addends, airheads, airheadz, baldheads, beachheads, bedspreads, bedsteads, beheads, besteads, bipeds, blackheads, block-heads, blockheads, bobsleds, boneheads, boreads, bowheads, bridgeheads, bulkheads, bunheads, calfed's, catheads, co-eds, coeds, cokeheads, cowsheds, crackheads, daybeds, deadheads, deathbeds, delmed's, dogsleds, drumheads, egghead's, eggheads, embeds, emeds, farmsteads, fatheads, flatbeds, flatbreads, flatheads, floorheads, foreheads, ghostheads, glenfed's, godheads, goodreads, hardheads, hogsheads, homefed's, homestead's, homesteads, hopheads, hotbeds, hotheads, imbeds, jarheads, lunkheads, mastheads, meatheads, oersteds, olmstead's, op-eds, oreades, oreads, outspreads, pitheads, potheads, purebreds, railheads, redheads, retreads, roadbeds, roundheads, seabeds, shortbreads, sickbeds, skinheads, snakeheads, soreheads, spearheads, steelheads, straightheads, streambeds, subheads, sunbeds, sweetbreads, tapeheads, thickheads, toonheads, towheads, warheads, wellheads, whitehead's, whiteheads, wingspreads, woodsheds, worsteds

3 syllables:
arrowheads, barrelheads, biomed's, buffleheads, chuckleheads, copperheads, curly-heads, dokumeds, dragonheads, dunderheads, featherbeds, fiddleheads, figureheads, flowerbeds, fountainheads, go-aheads, hammerheads, ironheads, knuckleheads, leatherheads, letterheads, loggerheads, lumileds, maidenheads, metalheads, metalheadz, muttonheads, newlyweds, overheads, overspreads, pistonheads, riverbeds, showerheads, sleepyheads, slugabeds, thoroughbreds, thunderheads, waterbeds, watersheds

4 syllables:
at loggerheads, eraserheads, propellerheads

6 syllables:
parallelepipeds