IPA phoneme /θ/

In English, both in Received Pronunciation and in General American, the IPA phonetic symbol /θ/ corresponds to the initial consonant sound in words like "think", and "thought" and the final one in "bath" and "both".

/θ/ is an unvoiced consonant; its voiced counterpart is IPA phoneme /ð/. Both phonemes are consistently spelled "th". See Decoding exercises: "th".

Common words
Initial pronunciation of /θ/: Final pronunciation of /θ/: Middle pronunciation of /θ/:
 * thanks - theater - theatre - theme - theory - therapy - thick - thin - thing - think - thirteen - thirst - thirty - thorough - thought - thousand - threat - three - threw - throat - through - throw - thumb - Thursday
 * bath - beneath - birth - both - breath - death - depth - earth - faith - forth - growth - health - length - math - month - mouth - north - path - smooth - south - strength - teeth - tooth - truth - wealth - worth - youth
 * anything - everything - nothing - something
 * athlete - author - Dorothy - Ethiopia /ˌiːθiːˈoʊpiːə/ - ethnic - healthy - hypothesis - Martha - mathematics - maths - method - monthly - strengthen - wealthy

Plurals
Irregular plurals of words ending in /θ/, as /ðz/
 * baths - mouths - paths - youths

Several plurals of words ending in /θ/ are pronounced as /ðz/ and also as /θs/
 * oaths - truths - wreaths

/θ/ or /ð/

 * booth - with


 * /ð/, /θ/ within - without

Homophones

 * threw - through

Anticipated pronunciation difficulties depending on L1
Preconceived ideas and other interferences from L1 obviously interfere in many cases with how students perceive - and pronounce - sounds/words in English. The following section aims to point out some of the most typical difficulties teachers and students may encounter regarding pronunciation.

Spain
Many speakers don't distinguish clearly between /θ/ and /ð/ and when they see "th" tend to pronounce it [θ], a sound which corresponds to the letter "z" in Spanish. This happens also when speaking Spanish: Madrid's inhabitants are notorious for pronouncing [ma'driθ].

Another difficulty is the tendency to pronounce the initial letter "c" as /θ/ in words like "city" and "centre".

Latin America
The /θ/ sound doesn't exist, and speakers tend to replace it by /s/ or /t/. However if another phoneme must be chosen it has been suggested to use /f/, for example pronounce "think" as instead of.