'odor' 和 'smell' 的区别
The difference between 'odor' and 'smell

'

odor:
特别不好闻的东西
something that smells really bad

smell:
能闻到的东西 （好不好闻都不管）
something you can smell (whether good or bad)

如/e.g.
That rubbish has such a bad odor (always bad)

This perfume smells so good! (Good)
Why do you always smell so bad? (Bad)

Hope this is helpful to the 同学 asking the question and to everyone else!