The words "synonym" and "conceit" are quite distinct in meaning.
"Synonym" refers to a word that has a similar meaning to another word. For example, "big" and "large" are synonyms. Synonyms are useful in language as they allow for variety in expression and can help to avoid repetition. They can enhance the richness and precision of our communication by providing different options to convey the same or similar ideas.
On the other hand, "conceit" has multiple meanings. It can mean excessive pride or self-esteem, a fanciful or elaborate metaphor or image, or a clever or witty idea. For instance, a person with conceit might think very highly of themselves and believe they are superior to others. In literature, a conceit can be a complex and creative comparison that surprises and engages the reader.
In summary, while "synonym" is related to language and the similarity of meanings between words, "conceit" has more to do with human qualities or literary devices and has a broader range of interpretations.