Create a global variable for yaml file?

I have a snippet of an automation that is used all over a particular yaml file.

  action:
    - service: humidifier.turn_off
      entity_id: humidifier.midea

    - delay:
        seconds: 5

    - service: humidifier.turn_on
    …
    …

I want to be able to use a variable instead of hard coding seconds 5 everywhere.

How can I create a variable mDelay and inside the yaml file define it to be 10 (and easily change it again in the text file anytime I please), and then how can I use mDelay in place of everywhere I hardcoded 5?

What I don’t want to do is create a Helper or other HA object and use the UI to set it. I want this all to exist inside the yaml file. You would think I’d have learned how to do this a long time ago. :slightly_frowning_face: