More about diction
Diction ultimately comes from Latin dictiō (inflectional stem dictiōn-) “speaking, act of speaking, (oracular) utterance, word, expression,” a derivative of the verb dīcere “to say, speak, talk.” Dictiō, though a word in general Latin vocabulary, is naturally connected very closely with rhetoric and law, two very important professions among the Romans. Dīcere, earlier deicere, comes from the very common Proto-Indo-European root deik- (also deig-), dik- (dig-) “to show, point out,” and appears in Greek deíknysthai “to show, point out,” Gothic ga-teihan “to show, make clear,” and German zeigen “to show.” The 13th-century English philologist, grammarian, and university professor John of Garland coined the word dictiōnārius as the title for one of his Latin textbooks in which he grouped lexical items thematically. Garland explained that his dictiōnārius was not based on the sense of dictiō as a single word, but dictiō in the sense of connected discourse. In the 14th century the Benedictine monk, translator, and encyclopedist Pierre Bersuire used the term dictiōnārium as the title for an alphabetical encyclopedia of the Vulgate (St. Jerome’s version of the Latin Bible, completed at the end of the 4th century). By the 15th century, dictiōnārium acquired the generalized sense “alphabetized wordbook.” Diction entered English in the 15th century.