Enter a clue or pattern or both:
The Clue
Bedrock (7 letter answer)
The Answer
HARDPAN
Tags
Notes
The answer HARDPAN is so rare that it appears less than once every 2500 puzzles.
Definition
HARDPAN as a noun:
1. (caliche, hardpan) = crust or layer of hard subsoil encrusted with calcium-carbonate occurring in arid or semiarid regions