口こう中ちゅう

noun, noun which may take the genitive case particle 'no'

inside of the mouth; oral cavity

Refers to the interior space of the mouth. Used in medical, dental, and everyday contexts.

• 口こう中ちゅうが乾かわいて仕し方かたがない。

  My mouth is unbearably dry.

• 口こう中ちゅうを清せい潔けつに保たもつことは虫むし歯ば予よ防ぼうに大たい切せつです。

  Keeping the inside of your mouth clean is important for preventing cavities.