WordNet records no synonym and no antonym for carina. It is the only member of each of its synsets, 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 keel-shaped constellation in the southern hemisphere; contains the star Canopus
any of various keel-shaped structures or ridges such as that on the breastbone of a bird or that formed by the fused petals of a pea blossom
Synonyms, antonyms and the broader and narrower relations for carina come from Princeton University’s WordNet. Full sources and licences.