Stinky means something has bad smell.

Nostril is either of the two openings in the nose.

Nasal cavity is the inside of your nose.

Receptor is a nerve ending that reacts to a change, such as heat or cold, in the body by sending a message to the central nervous system.

Trillion is a number with twelve zeros.

Sensitive means easily changed, or damaged, especially by a physical activity or effect.

Scent means a smell.

Odor means a bad smell.