Definitions
1.nounSomething that has been retrofitted
2.nounThe act of retrofitting
3.verbTo add or substitute new parts or components to some device, structure etc., that were not previously available; to modernize
4.verbTo fix an older version (or older versions) as part of the same process of fixing the newest version; to backport"The bug was so bad that we had to retrofit our patch to the last three releases, as well as the newest release."
5.adjectiveOf, relating to, or being a retrofit