glad vs thankful

glad is a noun but thankful is not a noun.

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

glad (noun)	thankful (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

glad (adjective)	thankful (adjective)
showing or causing joy and pleasure; especially made happy	feeling or showing gratitude
cheerful and bright
feeling happy appreciation
eagerly disposed to act or to be of service