WordNet records no synonym and no antonym for hypertext. It is the only member of its synset, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
machine-readable text that is not sequential but is organized so that related items of information are connected
“Let me introduce the word hypertext to mean a body of written or pictorial material interconnected in such a complex way that it could not conveniently be presented or represented on paper”
Synonyms, antonyms and the broader and narrower relations for hypertext come from Princeton University’s WordNet. Full sources and licences.