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capa f. (Noun) "cape"

10th cent. From Latin cappa 'id.,' first attested in the 6th cent. Of unknown origin. Suspiciously similar to other *kap(p)- roots in Italic. See also cabo.

Also the origin of the surname Capa.

Romance: Western Vulgar Latin: Asturian capa, Portuguese capa, Galician capa, Catalan capa, French chape, Italian cappa; Eastern Vulgar Latin: Aromanian capã, Romanian capă
capaz (Adjective) "capable"

15th cent. From Latin capacem, accusative of capax "capable," but originally "able to contain." From capere "to fit," "to hold" (see caber).

Also the origin of the surname Capaz, Capaces.
capitán m. (Noun) "captain"

14th cent. From Late Latin capitaneus "captain." From caput "head" (see cabo).

Also the origin of the surname Capitán.

A "Latinism," a late borrowing from Latin to name the role of a ship's captain.
capra f. (Noun) "goat"

From Latin capra "she-goat." From Proto-Italic *kapra- 'id.' Likely a loan from a non-Indo-European language. Note the variation between *ka- and *ga- in Celtic (Old Irish caera "sheep" versus gabor "roebuck").

Romance: Western Vulgar Latin: Asturian cabra, Portuguese cabra, Galician cabra, Catalan cabra, French chèvre, Italian capra; Eastern Vulgar Latin: Aromanian caprã, Romanian capră; Sardinian: craba

Italic: Umbrian kaprum

Indo-European: Celtic: Gaulish gabrus, Old Irish caera "sheep" (kapera-), gabor, Middle Welsh gauar, Old Breton gabr, Old Cornish gauar; Germanic: Old Norse hafr, Old English hæfer; Hellenic: Ancient Greek κάπρος (kápros) "boar;" Indo-Iranian: Sanskrit kápṛth? "penis"
cara f. (Noun) "face"

12th cent. From Latin cara 'id.,' from Greek κάρα (kára) "face," "head." Mycenaean ka-ra-. From Proto-Indo-European *ḱr̥h2r̥-(e)s-n "head."

Romance: Western Vulgar Latin: Asturian cara, Portuguese cara, Galician cara, Catalan cara; Extra-Comparanda: English charivari, shivaree (borrowed from French charivari of the same meaning, from Vulgar Latin caribaria "headaches," in reference to the loud, raucous noise of a charivari, borrowed from Ancient Greek καρηβαρία (karebaría) "headache," lit. "heavy head")

Italic: Latin cerebrum (whence cerebro)

Hellenic: Ancient Greek κέρας (kéras) "drinking horn," "horn trumpet" (ḱer-h2-s-)

Indo-European: Germanic: Old Norse hjarni "brain," Old English hærn (English harns); Armenian: sar; Indo-Iranian: Sanskrit śíras-, Young Avestan sarah-

Only Western Romance languages preserved the Latin word cara while Eastern Romance preferred the Vulgar Latin term *facia (also in Modern Spanish as faz).
carajo m. (Noun) "penis;" "crow's nest"

Unknown origin. A link to other Romance words for penis is plausible but shakey in which case we can posit a Vulgar Latin word *caraculus "little stick," which would have been a borrowing from Greek χάραξ (kháraks) "stick" with a diminutive suffix. χάραξ is of unknown origin. Possibly borrowed from a non-Indo-European language.

Romance: Western Vulgar Latin: Asturian (dialects) carayu, Portuguese caralho, Galician carallo, Catalan carall
caray (1) (Interjection) "oh!"

Taboo distortion of carajo.
caray (2), carey (Noun) "sea turtle;" "tortoise shell"

Early 16th cent. Borrowed from Dominican Republic Taino carey "sea turtle." In Taino, carey is specifically a salt-water turtle while a fresh-water turtle is a jicotea.
cárcel m. (Noun) "prison"

10th cent. Old Spanish cárcere 'id.' From Latin carcerem, accusative of carcer 'id.' From Proto-Italic *karkro- "enclosure." From Proto-Indo-European *kr̥-kr- 'id.,' a reduplication of a root *ker- "circle" that otherwise only attested in Greek. *ker- may have been a loanword.

Romance: Western Vulgar Latin: Asturian cárcel, (dialects) cárcere Portuguese cárcere, Galician cárcere, Italian carcere; Eastern Vulgar Latin: Romanian carceră

Indo-European: Hellenic: Ancient Greek καρκίνος (karkínos) "crab"
carecer (Verb) "to lack"

Early 15th cent. From Vulgar Latin carescere 'id.,' inchoative of Latin carerer 'id.' For the etymology of the inchoative verb-forming suffix, see -ecer. Latin carere is from Proto-Italic *kas-ē- 'id.' Of unknown origin.

Romance: Western Vulgar Latin: Asturian carecer, Portuguese carecer, Galician carecer

Italic: Oscan kasit "it must," Faliscan carefu "I will lack"