retroflex consonant

Subapical retroflex plosive

A retroflex (/ˈrɛtrəflɛks, -roʊ-/ ) consonant is a coronal consonant where the tongue has a flat, concave, or even curled shape, and is articulated between the alveolar ridge and the hard palate. They are sometimes referred to as cerebral consonants—especially in Indology. Other terms are domal and cacuminal (/kəˈkjuːmɪnəl/ ), though in rare cases either word can mean palatal consonants more broadly.