How to categorize 'perfect' and 'dead'? [duplicate]

Solution 1:

They are called ‘non-gradable adjectives’ (or ‘absolute adjectives’).

Non-gradable adjectives: absolute adjectives

Some adjectives are non-gradable. For example, something can't be a bit finished or very finished. You can't be a bit dead or very dead. These adjectives describe absolute qualities. To make them stronger we have to use modifiers like absolutely, totally or completely:

  • Thank you, I love it! It's absolutely perfect!
  • Their farm was totally destroyed by a tornado.
  • My work is completely finished. Now I can relax.

[British Council]