Atonic

A·ton·ic

Atonic

a.
  1. Characterized by atony, or lack of vital energy; as, an atonic disease. (Med.)
  2. Unaccented; as, an atonic syllable. (Gram.)
  3. Destitute of tone vocality; surd.

Atonic

n.
  1. A word that has no accent. (Gram.)
  2. An element of speech entirely destitute of vocality, or produced by the breath alone; a nonvocal or surd consonant; a breathing.
  3. A remedy capable of allaying organic excitement or irritation. (Med.)