Pervicacious is an adjective that means obstinate or extremely willful.

The Latin word vincere (VEEN chair ay) means ‘win.’ Our word of the day combines this word with the prefix P-E-R, meaning ‘thoroughly.’ You could say that a pervicacious person is someone who is thoroughly committed to winning all the time. For example: Grandpa’s pervicacious rejection of new technology made it difficult to teach him a new language. It wasn’t easy to find a Spanish lesson that I could play on a gramophone.