It’s a good old Anglo Saxon word, but it did not mean to grow angry, scowling, waiting the chance to strike. It meant, simply, to boil. Why didn’t the Anglo Saxons say boil if they meant boil? Or bo’ll, if they were from Southwark? Or berl, if they were from Brooklyn-on-the-Thames? They hadn’t been invaded by the French, that’s why. I suppose that English stewards cooking (a French word) soup (a French word) for their dukes (a French word) would boil it—seething with resentment. Boil comes from a stock of Latin / Romance words having to do with bubbling over: an ebullient man is the life of the party.
The old meaning of the word is preserved in the King James account of the manna from heaven: “Bake that which ye will bake today, and seethe that which ye will seethe” (Ex. 16:23). The past tense form wasn’t seethed , but sod (!): “And Jacob sod pottage; and Esau came from the field, and he was faint” (Gen. 25:29). That didn’t mean that Jacob sprinkled dirt into the stew. He sod the stew in a pot: he boiled it.
Strangely enough, we don’t have the old past form, but we do still have the past participle: sodden. But we don’t use it to mean boiled. Something is sodden when it is wet all through, usually miserably so: “I couldn’t wait to take off those sodden clothes.” Not boiled clothes, but sodden, and so almost as bad.