teaser
In the context discussed here, a teaser is a text that is displayed on websites and is intended to turn the reader into an interested party. The teaser is usually the first words or sentences of the entire text.
When the viewer has read the teaser, he can decide whether he is interested in the whole text. The teaser should briefly outline the topic, provide an overview and make the reader curious. Since the teaser is not a new text or a short version, the text used as a teaser should contain important statements about the whole article.
Teasers break off after a certain number of words or sentences and offer the user the option of clicking on a highlighted word such as "...more" to call up the entire text article.