prolongation

US /ˌproʊ.lɑːŋˈɡeɪ.ʃən/
UK /ˌproʊ.lɑːŋˈɡeɪ.ʃən/
1.

sự kéo dài

the act of making something last a longer time:

:
•
More research is being done into the prolongation of life.