a riblike part of a plant or animal (such as a middle rib of a leaf or a thickened vein of an insect wing)
"The botanist carefully traced the costa along the midrib of the large fern frond."
Synonym of rib.
"The surgeon carefully repaired the fractured costa to stabilize his broken back."
In plain English: A costa is the long, narrow strip of land along an ocean or sea.
"We spent our vacation relaxing on the sandy costa of California."
Usage: In everyday English, costa is not used as a synonym for rib; instead, it refers to a coastal region or strip of land bordering a sea. You will typically encounter this word in geographical names like Costa Rica or specific biological terms, rather than describing body parts.
A surname, from Romance languages.
"The award-winning chef Costa shared his family's secret recipe during the interview."
A Italian surname, from Italian.
"The Costa family has been running that local bakery for over three generations."
The word costa comes directly from the Latin term meaning "a rib." It entered English as a doublet of the more common word coast.