No audible release

No audible release
◌̚

A stop with no audible release, commonly called an unreleased stop, is a stop consonant with no release burst: no audible indication of the end of its occlusion (hold). In the International Phonetic Alphabet, lack of an audible release is denoted with an upper-right corner diacritic (U+031A ◌̚ COMBINING LEFT ANGLE ABOVE) after the consonant letter: [p̚], [t̚], [k̚].

Audibly released stops, on the other hand, are not normally indicated. If a final stop is aspirated, the aspiration diacritic ⟨◌ʰ⟩ is sufficient to indicate the release. Otherwise, the "unaspirated" diacritic of the Extended IPA may be employed for this: apt [ˈæp̚t˭].

In most dialects of English, the first stop of a cluster has no audible release, as in apt [ˈæp̚t], doctor [ˈdɒk̚tər], or logged on [ˌlɒɡ̚dˈɒn]. Although such sounds are frequently described as "unreleased", the reality is that the two consonants overlap so that the release of the first takes place during the hold of the second, masking the first consonant's release and making it inaudible. This can lead to cross-articulations that seem very much like deletions or complete assimilation. For example, hundred pounds may sound like [hʌndɹɨb pʰaundz] but X-ray and electropalatographic studies demonstrate that inaudible and possibly weakened contacts may still be made, so that the second /d/ in hundred pounds does not entirely assimilate a labial place of articulation, but rather co-occurs with it.

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