say it: KAW-stah
costa is a noun meaning "a riblike part of a plant or animal (such as a middle rib of a leaf or a thickened vein of an insect wing)". It carries 2 recorded senses.
a riblike part of a plant or animal (such as a middle rib of a leaf or a thickened vein of an insect wing)
vertebrate
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for costa come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.