| Noun | 1. | ageing - acquiring desirable qualities by being left undisturbed for some timemellowing - the process of becoming mellow biological process, organic process - a process occurring in living organisms |
| 2. | ageing - the organic process of growing older and showing the effects of increasing agecatabiosis - normal aging of cells biological process, organic process - a process occurring in living organisms | |
| Adj. | 1. | ageing - growing old old - (used especially of persons) having lived for a relatively long time or attained a specific age; "his mother is very old"; "a ripe old age"; "how old are you?" |