鼻び口こう

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

nose and mouth; muzzle

Refers to the nose and mouth area together, often used for animals (muzzle) or in medical/descriptive contexts for humans.

• 犬いぬの鼻び口こうに触ふれないでください。

  Please do not touch the dog's muzzle.

• 鼻び口こう周まわりのケアが大たい切せつです。

  Care around the nose and mouth area is important.

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

nostril; nostrils

Used in anatomical or formal contexts to mean nostril(s). In everyday speech, 鼻の穴 is more common.

• 解かい剖ぼう学がくでは、鼻び口こうは鼻び孔こうを指さすこともある。

  In anatomy, 鼻口 can refer to the nostrils.