What is the meaning of Fasti?

The calendar, which gave the days for festivals, courts, etc., corresponding to a modern almanac. They were generally engraved on stone, e.g. marble

Records or registers of important events (outside the dominion of Ancient Rome)

to fast

plural of fasto

inflection of fāstus:

1. nominative/vocative plural
2. genitive singular

nominative/vocative plural

genitive singular

stuck, tight, secured

fixed, unwavering

Source: wiktionary.org