noun

• The act of retaining or something retained
• The act or power of remembering things
• A memory; what is retained in the mind
• (medicine) The involuntary withholding of urine and faeces
• (medicine) The length of time an individual remains in treatment
• (obsolete) That which contains something, as a tablet; a means of preserving impressions.
• (obsolete) The act of withholding; restraint; reserve.
• (obsolete) A place of custody or confinement.
• (law) The right to withhold a debt, or of retaining property until a debt due to the person claiming the right is duly paid; a lien.
• (insurance) The portion of a potential damage that must be paid for by the holder of an insurance policy.