what does again and again mean?

AGAIN AND AGAIN as ADVERB

Meaning
- repeatedly
Synonym(s)
- over and over (what does over and over mean?)
- over and over again (what does over and over again mean?)
- time and again (what does time and again mean?)
- time and time again (what does time and time again mean?)
Usage Example(s)
- the unknown word turned up over and over again in the text