fast (2)EnglishOxford American Thesaurusfast2 verb three protesters fasted for three days and held a vigil outside the embassy.: abstain from food, refrain from eating, deny oneself food, go without food, go hungry, eat nothing, starve oneself; go on hunger strike. ▷antonyms eat; indulge oneself.noun a five-day fast: period of fasting, period of abstinence; hunger strike; diet. ▷antonyms feast.