What is the meaning of the word "convert"?

Definitions:

to cause to adopt a new or different faith verb
- The missionaries converted the Indian population
to change from one system to another or to a new plan or policy verb
- We converted from 220 to 110 Volt.
to change religious beliefs, or adopt a religious belief verb
- I converted to Buddhism.
to change the nature, purpose, or function of something verb
- convert lead into gold
to exchange or replace with another, usually of the same kind or category verb
- Could you convert my dollars into pounds?
to score an extra point or points after touchdown by kicking the ball through the uprights or advancing the ball into the end zone verb
- I converted and my team won.