Mild:
* Unpleasant: Suggests something that is simply not enjoyable or agreeable.
* Repulsive: Causes a feeling of aversion or dislike.
* Offensive: Insults or offends one's sensibilities.
* Nauseating: Causes a feeling of nausea or sickness.
* Unsavory: Suggests something that is morally or ethically questionable.
* Unpalatable: Refers to something that is not agreeable to the taste or mind.
Moderate:
* Loathsome: Causes intense aversion or disgust.
* Abhorrent: Strongly disliked or detested.
* Repugnant: Causes revulsion or disgust.
* Appalling: Causes shock or horror.
* Revolting: Causes a feeling of disgust or nausea.
Strong:
* Abominable: Despicable or hateful.
* Deplorable: Deserving strong condemnation.
* Execrable: Extremely bad or unpleasant.
* Grotesque: Disturbingly ugly or distorted.
* Hideous: Extremely ugly or repulsive.
* Odious: Extremely hateful or unpleasant.
* Scornful: Expressing or feeling contempt or disdain.
Informal:
* Yucky: Used to express a feeling of disgust or aversion.
* Gross: Used to express strong disgust.
* Ugh: An expression of disgust or aversion.
* Eww: A more informal version of "ugh".
* Sickening: Used to express a feeling of disgust or nausea.
* Creepy: Used to describe something that is unsettling or frightening.
The best word to use will depend on the specific context and the intensity of the feeling you want to convey.