delta vs Greek alphabet

delta and Greek alphabet both are nouns.

Word	Noun	Adjective	Verb	Adverb
delta	Yes	No	No	No
Greek alphabet	Yes	No	No	No

delta (noun)	Greek alphabet (noun)
the 4th letter of the Greek alphabet	the alphabet used by ancient Greeks
a low triangular area of alluvial deposits where a river divides before entering a larger body of water
an object shaped like an equilateral triangle