Lery wrote:It's the fact of "omitting" something.
In that case we are omitting words in a sentence because they are implied by the construction...
Example:
I'm going to the doctor's.
Here the "appointment" is implicit. So it's an ellipsis from Pudding's point of view... (Personally I'm using ellipsis only to indicate the narrative device of omitting a portion of the sequence of events, allowing the reader to fill in the narrative gaps.)
@Pudding : Sandy's (car) would also be called a genitive, wouldn't it ?
Yes, "Sandy's car" are genitives.
For ellipsis, you first have to provide sufficient information before the sentence. Then, you have to check if ambiguity is created in the ellipsis, which should be dismissed immediately if found. It's called lexical restriction.
In writing, for the sentence "I'm going to the doctor's", you would either have to, generally, provide the word 'appointment' beforehand or after the word "doctor's".
1. I was treated better during the dentist's appointment than during the doctor's. (comparative deletion)
2. On Friday, I'm going to the dentist's appointment, and on Monday the doctor's. (double ellipsis)
3. I'm going to the doctor's appointment. (no ellipsis)
In informal speech, though, I think it has been more common to use ellipsis without giving information beforehand. I often hear people say, "I'm going to Wendy's." or "I'm going to McDonald's." Blame these fastfood restaurants.