To completely ruin an essay by referring to a thesaurus for every other word, thus inserting words that you don't really understandthe definition of to make yourself appear smarter to the reader.
To replace words in a sentence, phrase, or song with other words that mean the same thing. Implies poor results, or dumbing down. This is a common practice among hymnal editors of some denominations, who are apparently among the most clueless humans walking the earth.