|Origin:||Latin conversio, from convertere; CONVERT1|
when you change something from one form, purpose, or system to a different one
The warehouse was undergoing conversion into apartments.
the conversion of waste into usable products
The British conversion to the metric system took place in the 1970s.
house/barn/loft etc conversion British English (=when you change the use of a house, barn etc, so that it becomes apartments, a house, a room etc)
when someone changes from one religion or belief to a different one
a conversion to vegetarianism
Newman's conversion from Anglicanism to Catholicism
a way of scoring extra points in rugby or American football