past tense vs preterit

past tense and preterit both are nouns.

Word	Noun	Adjective	Verb	Adverb
past tense	Yes	No	No	No
preterit	Yes	No	No	No

As nouns, preterit is a hyponym of past tense; that is, preterit is a word with a more specific, narrower meaning than past tense:

Other hyponyms of past tense include preterite, past simple, simple past.

past tense (noun)	preterit (noun)
a verb tense that expresses actions or states in the past	a term formerly used to refer to the simple past tense