What is the meaning of retroflex?

verb

• Bend or turn backward.
  • synonyms: replicate
• Articulate (a consonant) with the tongue curled back against the palate.
  • usage: "Indian accents can be characterized by the fact that speakers retroflex their consonants"

adjective

• Bent or curved backward.
  • synonyms: retroflexed
• Pronounced with the tip of the tongue turned back toward the hard palate.
  • synonyms: cacuminal