Classic board game and Tim Curry movie

noun

1. Something that guides through an intricate procedure or maze of difficulties
2. Idea, notion

   "had no clue what he meant"

verb

1. To provide with a clue
2. To give reliable information to

   "he clued me in on how it happened"

phrasal verb

1. To give information to (someone)

   "The public should be clued in to what's happening."

idiom

1. Use to say that one does not know (something)