The /v/ sound is spelled with <v>, <ve> or <vv> in navvy. The /n/ sound is spelled <n>, <nn> or <gn> in reign.
The contrast is between a labio-dental fricative and an alveolar nasal continuant, both voiced. It is not a problem for learners.
The only taboo word pairing is vigour/nigger.
Interesting pairs include:
avoid annoyed
captive captain
civility senility
devise denies
skivvy skinny
vicars knickers
votary notary
The mean density value is 1.6%. The list makes 132 semantic distinctions, a loading of 51%.
alive align Ave Ann avoid annoyed beeves beans bevy Benny brave brain braved brained braves brains braving braining calve Calne calve khan calves khans captive captain captives captains Cavan cannon Cavan canon cave cane caved caned caves canes caving caning cavern cannon caverns cannons cavern canon cavern canon chive chine chives chines civic cynic civics cynics civility senility cleave clean cleaved cleaned cleaves cleans cleaving cleaning cleaver cleaner cleavers cleaners clove clone cloves clones conserve concern conserved concerned conserves concerns conserving concerning cove Colne cove cone coves cones crave crane craved craned craves cranes craving craning Dave Dane devise denies devote denote devoted denoted devotes denotes devoting denoting dive dine dived dined dives dines diving dining diver diner divers diners divide denied dove done dove dun doves duns Dover donor drove drone droves drones Eve e'en five fine fives fines fiver finer gave gain grave grain graves grains greaves greens grieve green grieves greens grieving greening grieved greened grove groan groves groans hived hind hove hone Jove Joan knives nines lave lain lave lane laves lanes leave lean leaves leans leaving leaning leavings leanings levee Lenny lever leaner levity lenity levy Lenny live line lives lines loaves loans louvre lunar mauve moan mauves moans move moon moved mooned moves moons moving mooning movie moony navvy nanny navvies nannies of on over owner overs owners owns oaves pave pain paved pained paves pains paving paining prove prune proved pruned proves prunes proving pruning rave rain raved rained raves rains raving raining rave reign raved reigned raves reigns raving reigning rave rein raved reined raves reins raving reining rev Rennes rev wren revs wrens review renew reviewed renewed reviewing renewing reviews renews revved rend rive Rhine rived rind rove roan roves roans save sane save seine saves seines saved seined saving seining saver saner shove shun shoved shunned shoves shuns shoving shunning shrive shrine shrived shrined shrives shrines shriving shrining sieve sin sieved sinned sieves sins sieving sinning skivvy skinny slave slain spiv spin spivs spins stave stain staved stained staves stains staving staining stove stone stoves stones thereof thereon throve throne turves terns V knee V's knees vac knack vacs knacks vale nail vales nails vat Nat vat gnat vats gnats vector nectar veer near veered neared veering nearing veers nears veil nail veiled nailed veiling nailing veils nails veld knelt verse nurse versed nursed verses nurses verve nerve vest nest vested nested vesting nesting vests nests vet net vetted netted vetting netting vets nets vex necks vexed next Vic Nick vicars knickers vice nice vie nigh view knew view new viewed nude viewer newer views news vigour nigger vine nine vines nines voice Neuss vole knoll voles knolls votary notary votaries notaries vote note voted noted votes notes voting noting vow now vox knocks waive wain waives wains waive wane waives wanes waiving waning waived waned waive Wayne wave wain waves wains wave wane waves wanes waving waning waved waned wave Wayne weave wean weaves weans weaving weaning wharves warns whereof whereon wive whine wived whined wives whines wiving whining wive wine wives wines wiving wining wived wined
John Higgins, Shaftesbury, October 2010.