DeCosta
A surname usually built from a French-style “de + Costa,” meaning “of the coast” or from a place name with Costa.
The #9,861 most common surname in the United States (2010 Census) — about 1 in every 94,130 Americans shares it.
Etymology
DeCosta is generally understood as a reduced or Anglicized form of a surname built from the particle de/del/di plus Costa. In Romance languages, Costa usually means “coast” or can refer to a slope, hillside, or a place by the shore. The name may therefore have begun as a locational byname, indicating someone from a coastal place or a family identified with a place called Costa.
History
The 19th-century source excerpt links Decosta with forms such as De Coster and Decoster, suggesting that English-speaking recorders treated it as part of a larger family of continental surnames beginning with De-. In modern usage, DeCosta is found especially in North American records, where the spacing and capitalization often shifted over time as names were adapted to English spelling conventions.
Origin
Regions
Variant spellings
Fun fact
Because the prefix de was often merged or dropped in English records, the same family line could appear as De Costa, Decosta, or simply Costa in different documents.
From the historical record
“GAN, Deake, De Bank, De Brenner, De Carteret, Decastro, Decatur, Decker, De Colley, Decorsey, Decosey, De Coster (sometimes spelt Decosta), De CouRSEY, Decrow, Dede, Deegan, Deely, Deering, Defrees, De Freitas and De Frites, Degan, Deg- nan, Degran, Dehon, Deichert, Dejardin; Dela- hanty, Delanty, Delehante …”
— Suffolk Surnames (3rd ed.)