Other forms: conceits
Conceit is too high an opinion of yourself, or a fanciful idea. Insufferable conceit, a clever conceit, the central conceit.
The two senses are far apart and both are current: the vanity one is a straightforward vice, and the literary one names an extended and ingenious comparison — the metaphysical poets built whole poems on a single conceit. Of a film or novel, its conceit is the premise it asks you to accept. Note that conceit and concept are the same word.
1nounconceitToo high an opinion of yourself.
“His conceit made him unpopular, because he thought he was smarter than everyone else.”
2nouningeniousAn ingenious idea or premise.
“The novel's central conceit is that the whole story is told by a dog.”
conceit is vanity, or a fanciful idea.
Middle English conceyte comes from conceive, formed on the pattern of deceive and deceit. Concept is the same Latin word arriving directly.
Middle English
conceyte
English, today
conceit
From Middle English conceyte. From Middle English conceyte, formed from conceyven by analogy with pairs such as (Modern English) deceive~deceit, receive~receipt etc. a doublet of concept and concetto. Akin to Portuguese conceito.
Etymology from Wiktionary, CC BY-SA