Perfidious is an adjective that means deceitful and untrustworthy.

Our word of the day is derived from the Latin word perfidia (pair FEE dee uh) meaning ‘treachery.’ By the late 16th century, the word had found its way into the English language as ‘perfidy.’ Perfidious is the adjective version of it.

There is no room for perfidious behavior on this team. If we don’t have trust in our teammates, there is no way we can come together and win!