Smell

匂い

nioi

(sensation)

嗅覚

kyūkaku

(sense of smell)

匂いを感じる

nioi o kanjiru

(sense with nose)

匂う

niou

(to have a particular smell, whether good or bad; if descriptive, followed by "like" or "of")

嗅ぐ

kagu

(sense with nose)