I used to say it was "Pit dark" or Pit black instead of pitch when I was explaining how dark it was outside. I always thought it refered to how dark it was at the bottom of a bottomless pit.
A childhood belief about speaking

others believed things like this
- When i was a kid, i thought that the tv changed channels by dark magic.— Anna
- my best friend was so pale i thought she could glow in the dark— tattiebird
- Dark brown Smarties were poisonous.Anon
- I used to believe if you read a book in the dark, you would go blind.— Ellen
- I belived carrots made you see in the dark Anon
- if you read the bible in the dark your eyes would pop out— chriistabelle