noun
retention
rih-TEN-shun/rɪˈtenʃn/
The continued holding of something rather than releasing it.
The dam ensures water retention behind its solid barrier.

Etymology
The pieces express an act of holding back: keeping something rather than letting it go. Early English use included keeping fluids within the body; the selected sense applies that idea more generally to continued possession.
In context
does not have recruitment or retention challenges
More examples
- Regular review improves your retention of new information.
- Flexible schedules help improve employee retention.
- Fluid retention can cause swelling in your ankles.
- The policy requires retention of financial records for seven years.
Forms
retain verb — Keep something rather than let it go.