/ak'euh lay"zheuh, -zhee euh, -zee euh/ , n. Med.
inability of a circular muscle, esp. of the esophagus or rectum, to relax, resulting in widening of the structure above the muscular constriction.
[ 1910-15; A- 6 + Gk chálas ( is ) ( chala- (s. of chalân to loosen) + -sis -SIS) + -IA ]