Disgust is a strong feeling of aversion to something, and may include strong emotional and visceral reactions (including such things as vomiting, etc.)
According to Wikipedia:
Disgust is an emotional response of revulsion to something considered offensive, distasteful, or unpleasant. In The Expression of the Emotions in Man and Animals, Charles Darwin wrote that disgust is a sensation that refers to something revolting. Disgust is experienced primarily in relation to the sense of taste (either perceived or imagined), and secondarily to anything which causes a similar feeling by sense of smell, touch, or vision. Musically sensitive people may even be disgusted by the cacophony of inharmonious sounds. Research continually has proven a relationship between disgust and anxiety disorders such as arachnophobia, blood-injection-injury type phobias, and contamination fear related obsessive–compulsive disorder (also known as OCD).Disgust is one of the basic emotions of Robert Plutchik's theory of emotions and has been studied extensively by Paul Rozin. It invokes a characteristic facial expression, one of Paul Ekman's six universal facial expressions of emotion. Unlike the emotions of fear, anger, and sadness, disgust is associated with a decrease in heart rate.
"Disgust" is learned behavior, and for that reason it is "culture-bound" behavior. In different cultures (and often within one single culture) people are taught that different things are "disgusting". What may be "disgusting" to one person may be perfectly acceptable to another.
Sexophobes and antisexuals find a very large number of things--especially sexual behaviors--to be "disgusting". One may identify a person with serious psychological problems involving their own sexuality by how and what that person finds to be "disgusting".
Disgust is closely linked to what is considered to be "correct" morality in the minds of many people. If something is "disgusting" then, to them, it is "immoral". Many sexophobes and antisexuals are "disgusted" that BoyLovers find the bodies of boys to be aesthetically pleasing and even sexually attractive.
[Personally, this Editor finds the attitudes and behaviors of sexophobes and antisexuals to be extremely disgusting! Certainly, their attitudes, in terms of normal human behavior, are unnatural and quite immoral!]