You can use retention to mean the ability to keep or hold. If you have extraordinary powers of retention, you remember everything you hear or learn.

Are your ankles ever swollen after a long flight? This comes from the lack of movement which can cause the retention of water. The roots of the word, Latin re- "back" and tenere "to hold," say it all. You often use the word in the military or business contexts to talk about keeping soldiers, or employees, from leaving. If you're lucky, they might offer you a retention bonus to prevent you from quitting.

Definitions of retention

n the act of retaining something

holding, keeping
the act of holding back or keeping within your possession or control
the act of storing something
preservation and methodical arrangement as of documents and papers etc.
Type of:
ownership, possession
the act of having and controlling property

n the power of retaining liquid

retentiveness, retentivity
urinary retention
holding urine in the urinary bladder
Type of:
impermeability, impermeableness
the property of something that cannot be pervaded by a liquid

n the power of retaining and recalling past experience

memory, retentiveness, retentivity
anamnesis, recollection, remembrance
the ability to recall past occurrences
Type of:
faculty, mental faculty, module
one of the inherent cognitive or perceptual powers of the mind