[re.ten.tion] n [ME retencioun, fr. L retention-, retentio, fr. retinere to retain--more at retain] (14c) 1 a: the act of retaining: the state of being retained b: abnormal retaining of a fluid or secretion in a body cavity
2. a: power of retaining: retentiveness b: an ability to retain things in mind; specif: a preservation of the aftereffects of experience and learning that makes recall or recognition possible
3: something retained