/at"n ee/ , n.
1. Pathol. lack of tone or energy; muscular weakness, esp. in a contractile organ.
2. Phonet. lack of stress accent.
Also, atonia /euh toh"nee euh, ay toh"-/ .
[ 1685-95; atonia átonos unaccented, languid, lit., toneless. See A- 6 , TONE ]