antimnemonic

anti- +‎ mnemonic

antimnemonic (comparative more antimnemonic, superlative most antimnemonic)

1. Hard to remember, often intentionally so.

   Features that make a password good tend to make it antimnemonic as well, which is bad because a password should be memorized rather than written down.

   • 1998, Arthur Robert Jensen, The g factor: the science of mental ability:

     I have translated the symbols used by these German authors, which are antimnemonic for readers of English, to the initial letters...