Pronunciation: [ pleth-er-uh ]
Definition: noun
1: overabundance; excess
2: (medicine) an excess of bodily fluid; particularly blood

Origin: Mid 16th century; Greek
Etymology: via late Latin from Greek plēthōrē, from plēthein ‘be full’.
Usage:

Synonyms:
deluge
glut
overabundance
plenty
profusion
surfeit
Antonyms:
lack
need
scarcity
want
Example:
1: The little boy had a plethora of cars in his collection.
2: The surgeon discovered a plethora during the operation.