Cargo is Spanish, from cargar, "to load," from Late Latin carricare, "to load a wagon," which rests on Latin carrus, "wagon" — the same word that gives English car. English took it in the 1650s in its shipping sense, freight loaded on a vessel, which is how most Spanish and Dutch nautical vocabulary arrived.
The satisfying part is that English already had the same word by another road. French took carricare too and turned it into charge, which English borrowed in the 1200s. So cargo and charge are doublets: one word, two journeys, arriving four centuries apart with different jobs. That is a common shape in English, and it is why the language has so many near-synonyms of different weights — one came early through French, one came later from Spanish or straight from Latin.
cargo (n.) 1650s, "freight loaded on a ship," from Spanish cargo "burden," from cargar "to load, impose taxes," from Late Latin carricare "to load a wagon or cart," from Latin carrus "wagon" (see car ). The French cognate yielded English charge (n.); also compare cark . South Pacific cargo cult is from 1949. Cargo pants is attested from 1977, "loose-fitting casual pants with large pockets on the thighs;" they were named for the cargo pocket (by 1944), originally on military pants, so called for its carrying capacity. also from 1650s
cargo came in through Later and wider borrowings, and its spelling follows that family's conventions.
What gives it away on the page
| -o/-a endings, ll, rr, ny for ñ | Spanish — much of it from the Americas.tornado, cargo, plaza, armadillo, guerrilla, canyon, mosquito |
Placing it without the spelling
| an unstressed vowel on the end, in food, music, or weather | Italian or Spanishpiano, opera, tornado, cargo |
Later and wider borrowings in the spelling guide · guess another word's family