bedrock
US: /ˈbɛˌdɹɑk/
UK: /bˈɛdɹɒk/
UK: /bˈɛdɹɒk/
Advanced English dictionary
+ noun
1 [sing.] a strong base for sth, especially the facts or the principles on which it is based: The poor suburbs traditionally formed the bedrock of the party's support. + Honesty is the bedrock of any healthy relationship.
2 [U] the solid rock in the ground below the loose soil and sand: to reach / get down to the bedrock
