The spelling of /s/ is <s> initially or <c> in cymbal, and <s>, <ss> or <ce> medially or finally. The /Ɵ/ sound is spelled <th> throughout.
This contrast is between two voiceless fricatives. Among native speakers the replacement of /s/ with /Ɵ/ is known as a lisp (technically an interdental lisp) and is common among young children. The six-year-old Violet Elizabeth Bott in Richmal Crompton's Just William books is able to control William Brown with the threat "I'll thcream, then I'll thcream and I'll thcream and I'll thcream till I'm thick" (William in Trouble, 1927, p. 86). If it persists it is regarded as a speech defect and can be treated by speech therapists. It may be associated with effeminacy and was caricatured as aristocratic in eighteenth century comedy. Since rather few languages use /Ɵ/, the problem for EFL learners tends to be the reverse of the lisp, substituting /s/ for /Ɵ/.
Interesting pairs include:
ensues enthuse
Essex ethics
unsinkable unthinkable
useful youthful
Since /s/ is a common sound, the figure for the mean density is very low at 0.6%. The set makes 59 semantic contrasts, a loading of 61%. The relative scarcity of minimal pairs is slight evidence for the O'Connor hypothesis that language is self-repairing, since this is a troublesome distinction.
baas bath besought bethought Bros broth burst berthed bypass bypath cymbal thimble cymbals thimbles eights eighth ensues enthuse Erse earth Essex ethics face faith force forth frost frothed gross growth kiss kith Miss myth moss moth mouse mouth niece 'neath Norse north pass path Perth purse piss pith placing plaything placings playthings race wraith sane thane sank thank saw thaw sawing thawing sawn thorn seam theme seams themes seines thanes serum theorem sick thick sicken thicken sickened thickened sickening thickening sickens thickens sickly thickly sickness thickness sicknesses thicknesses sigh thigh sighs thighs sin thin sink think sinkable thinkable sinking thinking sinks thinks sinker thinker sinkers thinkers sin thin sins thins sinned thinned sinning thinning sinner thinner sinners thinners sluice sleuth soar thaw soared thawed soars thaws sole thole soles tholes some thumb song thong songs thongs sort thought sorts thoughts souse south suds thuds sues thews sum thumb sums thumbs summed thumbed summing thumbing sump thump sumps thumps sums thumbs sunder thunder sundered thundered sundering thundering sunders thunders surd third tense tenth tensely tenthly truce truth unsinkable unthinkable use youth useful youthful usefully youthfully usefulness youthfulness wits width worse worth Xmas Exmouth