SICK and ILL

Both of these words are most commonly used as adjectives, as in:

I feel sick.

Ed had to leave school early because he was ill.

In American English, these two words have more or less the same meaning – they refer to a feeling of being unwell, whatever the problem might be. On the other hand, in British English, they have more distinct (ялгаатай ) meanings. Sick most commonly refers to feeling as if you are going to vomit (бөөлжис ), as in:

I think I’m going to be sick.

…while ill refers to any other feeling of being unwell. However, there are some phrases which are commonly used where sick has a more general meaning. For example:

I’ve been off sick for ten days – meaning I haven’t been to work/school for ten days because I’ve been feeling unwell.

Sick can also be used as a noun to refer to vomit. For example:

If you have children, you can be sure that you will have to clear up some sick at least once during their childhood.

Difference between sick and ill?

Sick or ill, the words are to an extent interchangeable; one can say he is sick or he is ill. Although I personally would be more concerned about ill than about sick. Ill suggests something serious like a stroke whereas sick suggest a sore throat.

And feeling sick means feeling nauseous whilst feeling ill means feeling unwell.
So overall , ill is more serious, sick is more trivial.
But non-humans tend only to be sick eg a sick cow, a sick joke, a sick economy.


The above answer is true for American English; in Britain, you'd say "ill" when you have any kind of bodily distress, but "sick" usually means stomach sickness and vomiting. 

what is the difference between sick and ill?

Sick and ill are almost identical, although sick is usually describing minor(чухал биш , жижиг ) health problems and illness is usually used to describe terminal or serious health problems.

But many English speaking North Americans have chosen to use sick as slang (хар ярианы үгс ), to mean cool, awesome or wicked (another slang word).

Example: That skateboard trick was sick.
I have used it many times and not even realized I had used it.