WordNet records no synonym and no antonym for becker muscular dystrophy. 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.
a form of muscular dystrophy that sets in in adolescence or adulthood and progresses slowly but will affect all voluntary muscles; characterized by generalized weakness and muscle wasting that affects limb and trunk muscles first; similar to Duchenne's muscular dystrophy but less severe; inheritance is X-linked recessive (carried by females but affecting only males)
Synonyms, antonyms and the broader and narrower relations for becker muscular dystrophy come from Princeton University’s WordNet. Full sources and licences.