[{"Bold_text": "verb (used without object)", "List Items": ["to form pus; generate purulent matter; suppurate.", "to cause ulceration, as a foreign body in the flesh.", "to putrefy or rot.", "to rankle, as a feeling of resentment."]}, {"Bold_text": "verb (used with object)", "List Items": ["to cause to rankle:Malice festered his spirit."]}, {"Bold_text": "noun", "List Items": ["an ulcer; a rankling sore.", "a small, purulent, superficial sore."]}]