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IPA – number	130
IPA – text	θ
IPA – image
Entity	θ
X-SAMPA	T
Kirshenbaum	T
Sound sample (help·info)

The voiceless dental non-sibilant fricative is a type of consonantal sound used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is θ, and the equivalent X-SAMPA symbol is T. The IPA symbol is the Greek letter theta, which is used for this sound in Greek, and the sound is thus often referred to as "theta". It is familiar to English speakers as the 'th' in thing.

The dental fricatives are often called "interdental" because they are often produced with the tongue between the upper and lower teeth, and not just against the back of the teeth, as they are with other dental consonants.

Many languages, including widely-spoken ones such as German, Portuguese, Japanese, Mandarin Chinese, as well as all Slavic languages, some dialects of English, and the seseante dialects of Spanish, lack this sound. Speakers of such languages and dialects sometimes have difficulty producing or distinguishing it from similar sounds, and typically replace it with a voiceless alveolar fricative, voiceless dental plosive, or a voiceless labiodental fricative^{[citation needed]}.

Features of the voiceless dental fricative:

• Its manner of articulation is fricative, which means it is produced by constricting air flow through a narrow channel at the place of articulation, causing turbulence.
• Its place of articulation is dental which means it is articulated with the tongue on either the lower or the upper teeth, or both.
• Its phonation type is voiceless, which means it is produced without vibrations of the vocal cords.
• It is an oral consonant, which means air is allowed to escape through the mouth.
• It is a central consonant, which means it is produced by allowing the airstream to flow over the middle of the tongue, rather than the sides.
• The airstream mechanism is pulmonic egressive, which means it is articulated by pushing air out of the lungs and through the vocal tract, rather than from the glottis or the mouth.

• List of phonetics topics