plenitude
Meaning: an abundance
Usage: My grandmother was overwhelmed by the plenitude of tomatoes her garden yielded this season.
plethora
Meaning: an abundance, excess
Usage: The wedding banquet included a plethora of oysters piled almost three feet high.
inundate
Meaning: to flood with abundance
Usage: Because I am the star of a new sitcom, my fans are sure to inundate me with fan mail and praise.