Heated to the point that it glows with a visible red color.
The smith's apprentice was still wary of manipulating the red-hot metal.
The Iron of it ſelfe, though heate red hot, / Approaching neere theſe eyes, would drinke my teares, / And quench this fierie indignation, / Euen in the matter of mine innocence.c. 1596 (date written), William Shakespeare, “The Life and Death of King Iohn”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act IV, scene i], page 14, column 1:
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Heaped up upon the floor, to form a kind of throne, were turkeys, geese, game, poultry, brawn, great joints of meat, sucking-pigs, long wreaths of sausages, mince-pies, plum-puddings, barrels of oysters, red-hot chesnuts, cherry-cheeked apples, juicy oranges, luscious pears, immense twelfth-cakes, and seething bowls of punch, that made the chamber dim with their delicious steam.1843 December 19, Charles Dickens, “Stave Three. The Second of the Three Spirits.”, in A Christmas Carol. […], London: Chapman & Hall, […], →OCLC, page 77:
Among this nation of necromancers there was also one who had in his veins the blood of the salamanders; for he made no scruple of sitting down to smoke his chibouc in a red-hot oven until his dinner was thoroughly roasted upon its floor.1845, Edgar Allan Poe, The Thousand-and-Second Tale of Scheherazade:
[A] red-hot poker will burn you if you hold it too long; […]1865 November (indicated as 1866), Lewis Carroll [pseudonym; Charles Lutwidge Dodgson], “Down the Rabbit-Hole”, in Alice’s Adventures in Wonderland, London: Macmillan and Co., →OCLC, page 10:
The cat-heads had burned away, and the two red-hot anchors had gone to the bottom, tearing out after them two hundred fathom of red-hot chain.1898 September, Joseph Conrad, “Youth: a Narrative”, in Blackwood’s Edinburgh Magazine, volume CLXIV, number DCCCCXCV, New York, N.Y.: The Leonard Scott Publication Co., page 325, column 1:
She sits at the intersection of start-up investing and the fast-growing ecosystem of online creators, both of which are red hot.2021 September 1, Taylor Lorenz, “She’s the Investor Guru for Online Creators”, in The New York Times, →ISSN: