Slack voice

The term slack voice (or lax voice) describes the pronunciation of consonants with a glottal opening slightly wider than that occurring in normal full voice. Such sounds are often referred to informally as lenis or half-voiced. In Chinese, in many Australian languages and elsewhere the "intermediate" phonation type of slack stops confuses European listeners, so that different transcription systems may use /p/ or /b/ for the same consonant.

See: breathy voice, creaky voice