Vari - > varati
cobori -> coborati
dobori -> doborati
pari - > parati
The answer for your question is "Torrent"
So why does Japanese have multiple words for the same number? It's partly to do with superstition - “shi” sounds like the Japanese word for death and “ku” can mean suffering; “shichi” can also mean “place of death”.
*Since you did not attach the text, I cannot help you figure out which phrases suggest the meanings.* But I can still help you with the three different definitions of fix.
Definitions:
1) To repair something so that it works properly.
2) To attach something so that it won’t move.
3) To deal with or correct a problem.
Used in a sentence:
1) He went to fix his car.
2) She tried to fix the bird feeder into place.
3) He turned to his parents whenever he got into a fix.