I'd be curious if the definition has changed in the past year (word redefinition seems to a thing lately and it is Literally not for the better!).

Immunity obviously means being immune. Immune has a specific definition and that is not "helps sometimes".

https://www.collinsdictionary.com/us/dictionary/english/immu...

Resistance or, decreased susceptibility, or whatever other term you wish to use, is not the same as immunity.

Otherwise what word do we use for "immunity" now?