Often taken to be a denominative verb 'to make bright, enlighten' toProto-Italic*argu-(“bright”), fromProto-Indo-European*h₂érǵus(“white”), from*h₂erǵ-. Thus cognate with Ancient Greekἄργυρος(árguros) andHittite𒄯𒆠𒅖(ḫarkiš,“bright, white”). If so, compareEnglishdeclare(literally“to make clear”) for the sense development.^[1]

Duchesne-Guillemin, Laroche and Melchert reject the above etymology and instead comparearguo with the semantically better-fittingHittite[script needed](arkuwā(i)-,“state one's case, make a plea”).(Canthis⁽⁺⁾ etymology besourced?)

• (Classical Latin)IPA^(key):/ˈar.ɡu.oː/,[ˈärɡuoː]
• (modern Italianate Ecclesiastical)IPA^(key):/ˈar.ɡu.o/,[ˈärɡuo]

arguō (present infinitivearguere,perfect activearguī,supineargūtum);third conjugation

1. (to make clear to the mind): toclarify, tomakeplain; toassert,declare,prove,show

   Synonyms:affirmō,firmō,contendō,aiō,fīgō

2. toreprove,accuse,charge with

   Synonyms:accūsō,condemnō,crīminor,compellō,obloquor,obiectō,corripiō,arripiō,pulsō,incūsō,arcessō

   • Vulgate;Prōverbia, 9:8

     Nōlīarguere dērīsōrem nē ōderit tēargue sapientem et dīliget tē.

     Translation from American Standard Version:

     Reprove not a scoffer, lest he hate thee:Reprove a wise man, and he will love thee.

3. toblame,censure

   Synonyms:obiūrgō,castīgō,perstringō,īnsector,corripiō,exprobrō,accūsō,incūsō,damnō,obloquor,acclāmō,inclāmō,increpō,animadvertō,reprehendō,compellō

4. todenounce as false
5. toargue, toallege; todisclose; tocomplain of, convict

• “arguo”, inCharlton T. Lewis and Charles Short (1879)A Latin Dictionary, Oxford: Clarendon Press
• “arguo”, inCharlton T. Lewis (1891)An Elementary Latin Dictionary, New York: Harper & Brothers
• arguo inGaffiot, Félix (1934)Dictionnaire illustré latin-français, Hachette.

arguo

1. first-personsingularpresentindicative ofarguir