No. Blowing up Suleimani with a predator drone was not an assassination. No. Blowing up Saleh al-Arouri with a drone was not an assassination.

Assassination requires a scheme or subterfuge. It's creeping up on someone or setting up for the perfect moment. An entire military department directing a distance strike at a convenient moment is not an assassination, it is an act of war.

Assassination is ALSO generally an act of war but the method and context is different.