rejuvenescence noun. 
[rɪ,dʒu:vɪ'nɛs(ǝ)ns] M17.[formed as REJUVENESCE + -ESCENCE.]1.  A physical, mental, or spiritual renewal of youth. 
M17.2.  Biology. The process by which a vegetative cell transforms itself into a new one. 
M19.Also 
 ■   rejuvenescency noun M17-L18.  [TahlilGaran] English Dictionary ▲