[TA] the anteroposterior curve or angle, with convesity directed anteriorly, of the anorectal junction; tonus of the puborectalis (muscle) produces the angle for maintaining fecal continence; relaxation of the muscle allows the angle to be reduced for defecation. SYN: flexura anorectalis [TA], flexura perinealis (canalis ani)*, perineal flexure of anal canal*, anorectal angle, perineal flexure of rectum.