Holy Trinity vs Lord

Holy Trinity and Lord both are nouns.

Word	Noun	Adjective	Verb	Adverb
Holy Trinity	Yes	No	No	No
Lord	Yes	No	No	No

As nouns, Lord is a hypernym of Holy Trinity; that is, Lord is a word with a broader meaning than Holy Trinity:

Other hypernyms of Holy Trinity include Almighty, Creator, Divine, God Almighty, Godhead, Jehovah, Maker.

Holy Trinity (noun)	Lord (noun)
the union of the Father and Son and Holy Ghost in one Godhead	a titled peer of the realm
	terms referring to the Judeo-Christian God