Or a word to describe the act of inaccurately using complicated or unusual words (often in an attempt to sound more intelligent)?
I considered 'bombastic' but it doesn't have that quality of inaccuracy.
Learn English – word to describe someone who often inaccurately uses words
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Best Answer
The act of using a word inaccurately could be called catachresis. Catachresis is defined as: "the misuse or strained use of words, as in a mixed metaphor, occurring either in error or for rhetorical effect." Or as: "The use of a word in a way that is not correct, for example, the use of mitigate for militate.
It has the adjective form of catachrestic.
This entry in Wikipedia says catachresis can be either unintentional or intentional. It's a fun word to say. Just be sure YOU use it correctly.