(~s)
1.
Conversion is the act or process of changing something into a different state or form.
...the ~ of disused rail lines into cycle routes...
A loft ~ can add considerably to the value of a house.
N-VAR: usu with supp
2.
If someone changes their religion or beliefs, you can refer to their ~ to their new religion or beliefs.
...his ~ to Christianity...
It’s hard to trust the President’s ~.
N-VAR: usu with supp, oft with poss