Is there any different between ta3udd and ta3uddiin?
The first is used when addressing a male person and the second when addressing a female person.
Well, a masculine entity and a feminine entity. A poet/orator could address a rose (assuming it's feminine in Arabic?) or a city (I know that's feminine ;) ).
مِنْ ١ (واحِدٍ)
It should be "min waaHid(in)" -- and not "min waaHid(un)". It is a fault of the voice.