腦海

脑海
nǎohǎi
  1. the mind
  2. the brain

CEDICT

Entry Composition

1 腦 nǎo
  1. brain
  2. mind
  3. head
  4. essence
2 海 hǎi
  1. ocean
  2. sea
  3. great number of people or things
  4. (dialect) numerous

classifiers: 個, 片