WordNet records no synonym and no antonym for spore. 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 small usually single-celled asexual reproductive body produced by many nonflowering plants and fungi and some bacteria and protozoans and that are capable of developing into a new individual without sexual fusion
“a sexual spore is formed after the fusion of gametes”
Synonyms, antonyms and the broader and narrower relations for spore come from Princeton University’s WordNet. Full sources and licences.