acute (adj.)

One of the features of sound set up by Jakobson and Halle in their DISTINCTIVE FEATURE theory of PHONOLOGY, to handle variations in PLACE OF ARTICULATION; its opposite is GRAVE. Acute sounds are defined articulatorily and ACOUSTICALLY as those involving a medial articulation in the VOCAL TRACT, and a concentration of acoustic energy in the higher frequencies; examples of [+acute] sounds are FRONT VOWELS, and DENTAL, ALVEOLAR and PALATAL CONSONANTS.