The spelling of /d/ in this list is <d> or <dd>. The /f/ sound is spelled <f>, <ff>, <ph> or <gh> in cough. Notice how the homograph does makes pairs with foes and fuzz and the homograph read makes pairs with reef and ref.
The contrast is between a voiced plosive and a voiceless fricative, well separated in the mouth. It is not a problem for learners.
Taboo word pairs include dart/fart and duck/fuck.
The phrase "dual fuel" has become familiar through cookers and domestic heating systems that can use electricity or gas. One pair of arguable status is handle/handful, where the /d/ in handful is elided between the other consonants. Other interesting pairs include:
carded Cardiff
cider cipher
Dallas phallus
digit fidget
doormat format
handle handful
inedible ineffable
liquidize liquefies
odysseys offices
radish raffish
tarried tariff
The mean density value is 2.9%. The list makes 233 semantic distinctions, a loading of 58%.
adore afore adored afford aided aphid allude aloof Auden orphan bead beef beading beefing beads beefs beady beefy bid biff bidding biffing bids biffs blood bluff blooding bluffing bloods bluffs breed brief breeding briefing breeds briefs breeder briefer bud buff budding buffing buds buffs cad caff cads caffs card calf carded Cardiff Chard chaff cider cipher ciders ciphers cod cough condign confine creed Crieff cud cuff D fee D's fees dab fab dace face dad fad dads fads daddy faddy Dail foil dairy fairy dairies fairies daisies phases dale fail dales fails Dallas phallus dame fame Dan fan Dane fain Dane feign Danes feigns Danny fanny dare fair dares fairs dare fare dared fared daring faring dares fares dart fart darted farted darting farting darts farts date fate dates fates dated fated date fête dated fêted dates fêtes dating fêting daw faugh daw for daw fore daw four daws fours dawn faun dawns fauns dawn fawn dawned fawned dawning fawning dawns fawns day fey days phase Dayton phaeton daze phase dazed phased dazing phasing dazes phases dead deaf dead fed deaden deafen deadened deafened deadening deafening deadens deafens deal feel deals fels dealing feeling dealings feelings deals feels dealt felt dealer feeler dealers feelers dear fear dears fears dearth firth dearths firths deb Feb debtor fetter debtors fetters deduce diffuse deed feed deeds feeds deign fain deign feign deigned feigned deigning feigning deigns feigns dell fell dells fells den fen dens fens dense fence denser fencer Derry ferry Des fez dew few DG Fiji Di fie Di phi dial file dials files dial phial dials phials diary fiery dibber fibber dibbers fibbers diction fiction diddle fiddle diddled fiddled diddles fiddles diddling fiddling die fie die phi dig fig digs figs digger figure diggers figures digit fidget digits fidgets Dilys Phyllis din fin dins fins din Finn dins Finns dine fine dined fined dining fining dines fines dined find diner finer dingle Fingal dire fire dish fish dishing fishing dishes fishes dishy fishy dishier fishier dishiest fishiest dive five dives fives diver fiver divers fivers dixies fixes dizzies fizzes dizzy fizzy dizzier fizzier dizziest fizziest do foe docks fox dodder fodder doe foe does foes does fuzz dog fog dogging fogging dogs fogs dogged fogged doggie foggy dole foal doled foaled doles foals doling foaling dolly folly dollies follies dome foam domed foamed domes foams donned fond door faugh door for door fore door four doors fours doorman foreman doormen foremen doormat format doormats formats Dorking forking dorm form dormant formant dormer former dorsal foresail Dorset faucet doss fosse dosses fosses dost fussed Doug fug downed found drank frank dread Fred drench French dray fray drays frays drier friar driers friars drier fryer driers fryers drill frill drilled frilled drills frills drivel frivol drivelled frivolled drivelling frivolling drivels frivols drizzle frizzle drizzled frizzled drizzles frizzles drizzling frizzling drown frown drowned frowned drowning frowning drowns frowns drowsy frowzy dry fry dried fried drying frying dries fries dual fuel duck fuck ducked fucked ducking fucking ducks fucks dude feud dudes feuds due few duel fuel duelled fuelled duelling fuelling duels fuels dues fuse dug fug dugs fugs dunk funk dunked funked dunking funking dunks funks dunned fund durst first dusty fusty dyer fire dyers fires Ed F endorse enforce endorsed enforced endorsement enforcement endorses enforces endorsing enforcing endues infuse feed feoff fill dill flood fluff flooding fluffing floods fluffs gad gaff gads gaffs gulled gulf handle handful hard half hardback halfback hardbacks halfbacks hard-baked half-baked header heifer headers heifers id if inedible ineffable lard laugh larding laughing lead leaf leading leafing lied life limbed lymph liquefies liquidize load loaf loading loafing loads loafs loader loafer loaders loafers lode loaf mud muff muddle muffle muddled muffled muddles muffles muddling muffling odd off odder offer ode oaf odes oafs odysseys offices owed oaf Phil dill piddle piffle piddled piffled piddles piffles piddling piffling predatory prefatory produce profuse prod Prof prude proof quad quaff quads quaffs quid quiff quids quiffs raddle raffle raddled raffled raddles raffles radish raffish read reef reads reefs read ref reader reefer readers reefers reading reefing reads reefs reed reef reeds reefs rid riff rids riffs riddle riffle riddled riffled riddles riffles riddling riffling ride rife rood roof rood-tree roof-tree rood-trees roof-trees rudder rougher ruddle ruffle ruddled ruffled ruddles ruffles ruddling ruffling Ryde rife sadist safest soldered Salford scarred scarf scud scuff scudding scuffing scuds scuffs surd serf serried serif she'd sheaf shelled shelf skid skiff soda sofa sodas sofas sodden soften starred staff standard Stanford stone-dead stone-deaf stride strife stud stuff studding stuffing studs stuffs study stuffy tarried tariff toddy toffee toddies toffees trod trough turd turf waddle waffle waddled waffled waddles waffles waddling waffling wade waif wades waifs wader wafer waders wafers ward wharf weighed waif who'd hoof wide wife widely wifely wooed woof
John Higgins, Shaftesbury, February 2010.