The /e/ vowel is spelled <e>, <ea> in death, exceptionally with <a> in any and says, and occurs in the letter names L, N and X. The vowel /3/ is usually spelled with <er>, <ir>, <ur>, <ear> as in dearth, <or> in word and world and <ol> in colonel.
Interesting pairs include:
descend discerned
kennel colonel
overhead overheard
secular circular
The mean density is 2.2%. The pairs make 94 semantic contrasts, giving a loading of 61%.
any Ernie beck burke becks burkes bed bird beds birds beg berg begs bergs beggar burgher beggars burghers belly Burley ben Bern ben burn bens burns bend burned bent burnt Benny Bernie best burst besting bursting bests bursts Betty Bertie bled blurred death dearth deaths dearths Debbie derby debt dirt Dec dirk deck dirk decks dirks descend discerned end earned Ed erred edge urge edged urged edges urges edging urging edgings urgings egg erg eggs ergs ego ergo Ellie early feather further feathered furthered feathering furthering feathers furthers fell furl felled furled felling furling fells furls fellow furlough fellows furloughs fem firm fen fern fens ferns ferry furry fez firs gem germ gems germs get girt head heard head herd headed herded heading herding heads herds held hurled hell hurl hells hurls hen Herne inset insert insets inserts intend interned Jenny journey jennies journeys kennel colonel kennels colonels kettle kirtle kettles kirtles L earl lecher lurcher lechers lurchers Len learn lend learned lens learns Lent learnt L's earls messy mercy Messrs mercers metal myrtle metals myrtles N earn N's earns ness nurse nesses nurses nest nursed nestling nurseling overhead overheard peck perk pecked perked pecking perking pecks perks pest pursed pet pert S Erse says sirs seabed seabird seabeds seabirds secular circular sedge serge sedges surges sever server severs servers sled slurred sped spurred spend spurned stead stirred steady sturdy steadier sturdier steadiest sturdiest steadily sturdily steadiness sturdiness Sten stern swell swirl swelled swirled swelling swirling swells swirls tech Turk techs Turks ten tern tens terns ten turn tens turns tend turned tenner turner tenners turners Tess terse vest versed wed whirred wed word wedded worded wedding wording weds words weld whirled weld world welds worlds well whirl welling whirling wells whirls went weren't west worst wet wert X irks yelling yearling yen yearn yens yearns
Credit: John Higgins