sesquipedalian vs pretentious

sesquipedalian is a noun but pretentious is not a noun.

Word	Noun	Adjective	Verb	Adverb
sesquipedalian	Yes	Yes	No	No
pretentious	No	Yes	No	No

sesquipedalian (noun)	pretentious (noun)
a very long word (a foot and a half long)

sesquipedalian (adjective)	pretentious (adjective)
(of words) long and ponderous; having many syllables	making claim to or creating an appearance of (often undeserved) importance or distinction
given to the overuse of long words	intended to attract notice and impress others
	(of a display) tawdry or vulgar