“The flu vax is a dead virus”
The most modern ones don’t even use the full virus. Just a protein from it that your immune system will learn to target as the enemy.
What’s funny about the terminology “dead virus” is that biology doesn’t consider viruses to ever be living organisms. It’s just a term of convenience. “Crippled virus” is probably more accurate.
The term of art today is, I believe, 'Inactivated Virus'.