rare metallic element, 1832, Modern Latin, named by its discoverer, Swedish chemist Jöns Jakob Berzelius (1779-1848) from thorite (silicate of thorium), the name of a mineral found in Norway from which it was extracted (which Berzelius had also named, as thoria, in 1828), and named in honor of the Scandinavian god Thor. With metallic element ending -ium.
fifth day of the week, Old English þurresdæg, a contraction (perhaps influenced by Old Norse þorsdagr) of þunresdæg, literally "Thor's day," from Þunre, genitive of Þunor "Thor" (see thunder (n.)); from Proto-Germanic *thonaras daga (source also of Old Frisian thunresdei, Middle Dutch donresdach, Dutch donderdag, Old High German Donares tag, German Donnerstag, Danish and Swedish Torsdag "Thursday"), a loan-translation of Latin Jovis dies "day of Jupiter."
Roman Jupiter was identified with the Germanic Thor. The Latin word is the source of Italian giovedi, Old French juesdi, French jeudi, Spanish jueves, and is itself a loan-translation of Greek dios hēmera "the day of Zeus."
fem. proper name, 13c., from earlier Aldreda (11c.), contracted from Etheldreda, a Latinized form of Old English Æðelðryð, literally "noble might," from æðele "noble" (see atheling) + ðryð "strength, might," from Proto-Germanic *thruthitho- "strength" (source also of Old Norse Þruðr, name of the daughter of Thor). Popularized by the reputation of Saint Etheldreda, queen of Northumbria and foundress of the convent at Ely.
mid-13c., from Old English þunor "thunder, thunderclap; the god Thor," from Proto-Germanic *thunraz (source also of Old Norse þorr, Old Frisian thuner, Middle Dutch donre, Dutch donder, Old High German donar, German Donner "thunder"), from PIE *(s)tene- "to resound, thunder" (source also of Sanskrit tanayitnuh "thundering," Persian tundar "thunder," Latin tonare "to thunder"). Swedish tordön is literally "Thor's din." The unetymological -d- also is found in Dutch and Icelandic versions of the word (compare sound (n.1)). Thunder-stick, imagined word used by primitive peoples for "gun," attested from 1904.