happy vs glad

happy is not a noun while glad is a noun.

Word	Noun	Adjective	Verb	Adverb
happy	No	Yes	No	No
glad	Yes	Yes	No	No

As adjectives, happy and glad are synonyms defined as:

happy (noun)	glad (noun)
	any of numerous plants of the genus Gladiolus native chiefly to tropical and South Africa having sword-shaped leaves and one-sided spikes of brightly colored funnel-shaped flowers; widely cultivated

happy (adjective)	glad (adjective)
enjoying or showing or marked by joy or pleasure	showing or causing joy and pleasure; especially made happy
well expressed and to the point	cheerful and bright
marked by good fortune	feeling happy appreciation
eagerly disposed to act or to be of service	eagerly disposed to act or to be of service