Collins English-English Dictionary

fester ['fεstə]

1. 1. vb to form or cause to form pus

2. 2. vi. [intr] to become rotten; decay

3. 3. vi. to become or cause to become bitter, irritated, etc, esp over a long period of time; rankle

   resentment festered his imagination

4. 4. vi. [intr] [Spoken] to be idle or inactive

5. 5. n a small ulcer or sore containing pus

6. 6. n [Etymology] C13: from Old French festre suppurating sore, from Latin: fistula

7. 7. n hasten slowly