Varro, De Lingua Latina 6.61-2
“The Latin verb dico has a Greek origin, the Greek verb deiknuô which means “to show”. From this meaning, as well, comes dicare “to show, dedicate” as when Ennus writes: “I say that this circus has six little turning posts.” From this word as well we get iudicare, “to judge” because the ius “right thing” is spoken. And from this we get iudex because the judge speaks the judgment (ius dicat) once he has the authority. From the same place, we have dedicate because the ending comes from speaking (Dicendo) certain words. Thus when a temple is dedicated by a magistrate it is done by speaking after the pontiff. From dicere, from speaking, is indicium (“information”); from this he declares war (indicit); “has invited people” to a funeral (indixit), he has postponed a day (prodixit), he has submitted a judgment (addixit). From this root as well we have named a dictum (“saying”) from farce and also the adjective dictiosus (“witty”). From this root we also have dicta, orders given by leaders in a military cample; and we also have dictata, dictation exercises in school. And we also have dictator as leader of the people because he must be called (dici) by the counsel. Some old phrase come from this too such as addici nummo (“to be betrayed for a penny”) or dicis causa “for the sake of judicial precedent” and addictus, to be bound to someone.”
Dico originem habet Graecam, quod Graeci deiknyo. Hinc etiam dicare, ut ait, Ennius:
Dico VI hunc dicare circum metulas.
Hinc iudicare, quod tunc ius dicatur; hinc iudex, quod ius dicat accepta potestate; hinc dedicat, id est quibusdam verbis dicendo finit: sic, enim aedis sacra a magistratu pontifice praeeunte, dicendo dedicatur. Hinc, ab dicendo, indicium; hinc illa: indicit bellum, indixit funus, prodixit diem, addixit iudicium; hinc appellatum dictum in mimo, ac dictiosus; hinc in manipulis castrensibus dicta ab ducibus; hinc dictata in ludo; hinc dictator magister populi, quod is a consule debet dici; hinc antiqua illa addici numo et dicis causa et addictus.