Interdental fricatives /θ/ and /ð/

 

Interdental fricatives /θ/ and /ð/ 

The /θ/ and /ð/ sounds are produced by the ‘TH’ spelling. /θ/ is voiceless, and /ð/ is voiced. To pronounce the /θ/ and /ð/ sounds, the tongue should be in between the teeth, thus these sounds are called the interdentals. The sound is made by lightly blowing out against teeth and the tongue, thus being fricatives. The back of your tongue is kept low and flat. 

/θ/, /ð/ words

These are words with voiceless ‘TH’, /θ/ : 

think, thin, thing, thanks, thirty, Thursday, three, thumb, third, thirteen, bathtub, toothpick, birthday, healthy, something, anything, athlete, math, tooth, teeth, tenth, ninth, breath, earth, mouth, south, north

 

These are words with voiced ‘TH’, /ð/ : 

then, than, those, worthy, mother, father, farther, northern, nevertheless, feather, weather, brother, clothing, clothes, either, another, neither, bathe, breathe, clothe, smooth

These are sentences with /θ/ and /ð/:

They think the athlete's birthday is this Thursday.

The brother will be thirteen this Thursday. 

They can clean their teeth with a thin toothpick.

They should ask their father, their mother or their brother.

The other clothes are smooth.

There is another feather over there.

That thing is thicker than that thin thing.

There is something in that dog's mouth.

My brother said the weather is warmer in the south than in the north.

The TH pair has no minimal pairs. Both /θ/ and /ð/ are uncommon sounds in many languages, and so are often confused with other sounds in proximity and voicing. /θ/ is often confused with nearby /f/, /t/, /s/, and /ð/ is often confused with /d/ and /z/. In this section, we examine the minimal pairs of these sounds: /θ/ and /f/; /θ/ and /t/; and /ð/ and /d/. In the next section where we introduce /s/ and /z/ sounds, we examine the remaining confusing pairs: /s/ and /θ/, and /z/ and /ð/.

/f/, /θ/ minimal pairs

/f/ and /θ/ are voiceless fricatives. They differ only at the place of articulation. /f/ is produced with upper teeth and lower lip, and /θ/ is produced with the tongue between the teeth. These are the minimal pairs: 

free three

deaf death

fought thought

fin thin

fresh thresh

freeze threes

fro throw

froze throws

fief thief

frill thrill

furred third