Other forms: loathing, loathed, loathes
To loathe something is to hate it so completely that being near it turns your stomach. The smell at the fish counter, the sound of someone chewing beside you, a voice on the radio you cannot sit through.
It is stronger than dislike and more physical than hate, because you loathe what disgusts you. It takes a plain object or an -ing form: she loathes small talk, he loathes standing in queues. The noun is loathing, the adjective is loathsome, as in a loathsome little man, and self-loathing turns the whole thing inward. The real trap is loath, spelled without the e and said with a soft th, which means reluctant, as in I am loath to ask her again. One letter apart, and almost opposite in feeling: loath is polite hesitation, loathe is disgust.
Loathe is homegrown and very old: Old English lathian, from Proto-West Germanic laithen and Proto-Germanic laithana, reaching Middle English as lothe. Norse took the same word as leida, and it lives on in Danish and Icelandic, while German kept Leid from the same family. There is no Latin anywhere near it, which is true of most of the blunt English feelings.
Proto-Germanic
*laiþāną
Proto-West Germanic
*laiþēn
Old English
lāþian
Middle English
lothe
English, today
loathe
From Middle English lothe, from Old English lāþian, from Proto-West Germanic laiþēn, from Proto-Germanic laiþāną. Cognate with Old Norse leiða (> Danish lede, Icelandic leiðast, all reflexive), German Leid.
Etymology from Wiktionary, CC BY-SA