by circumlocution with the verbs in To RETAIN.A retentive memory, memoria bona (Cic., Att.), tenax: a more retentive memory, memoria melior (Cic.): a very retentive one, tenacissima (Quint.): to have a retentive memory, memoria valere, vigere. If preceded by “so” - (that), tantus. Anybody had so retentive a memory, that, alicui memoria tauta fuit, ut, etc. (e.g., Hortensio, Cic.).