portable has no recorded synonym. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is unportable.
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.
easily or conveniently transported
“a portable television set”
a small light typewriter; usually with a case in which it can be carried
1 of the 3 recorded senses carries no synonym, antonym or related term, so it is not shown above. Every sense, with its definition and examples, is on the full entry for portable.
Synonyms, antonyms and the broader and narrower relations for portable come from Princeton University’s WordNet. Full sources and licences.