A device to add odor to a gas.

plural of odorizer

Having a distinctive odor.

Having an odour/odor.

Any substance that has a distinctive smell, especially one added to something (such as household gas) for safety purposes

plural of odorant

(obsolete) A fragrant substance; perfume.

(obsolete) odorous

Any smell, whether fragrant or offensive. / (figuratively) A strong, pervasive quality. / (figuratively, uncountable) Esteem. / (now rare) Something which produces a scent; incense, a perfume.

plural of odor