The word you’re looking for is: archaism.Definition:An archaism is a word, phrase, or expression that was once common in older literature or in texts like the Bible, but is no longer used in modern everyday language.Example archaic words: • Thou (you) • Hast (have) • Art (are) • Thine (yours) • Woe betide (something bad will happen)In a sentence:The word “thou” is an archaism often found in the King James Bible.