cunctus

Latin

Uncertain. Proposals include:

From concitus by syncope per Pokorny (1959), accepted by De Vaan (2008) with some reservations.^[1]^[2] Ernout and Meillet (1985) reject this etymology, and also reject the ancient etymology from co(n)iūnctus.^[3]
According to Sihler (1995), from Proto-Indo-European *ponkʷ-u- (“whole, entire”), which he reconstructs as the ancestor also of Hittite 𒉺𒀭𒆪𒍑 (pa-an-ku-uš, “whole, entire; senate”) and Hittite (pa-an-kur, “family, relations”), as well as the middle part of Ancient Greek ἅπαξ (hápax, “singly”).^[4] The Latin form would then show the same /p – kʷ > kʷ – kʷ/ assimilation as in quīnque. De Vaan rejects this etymology, saying that based on its genitive singular form pankawaš, Hittite pankuš cannot be cognate to Latin cū̆nctus and is more likely related to Sanskrit बहु (bahu).
From Proto-Indo-European *ponkʷ-to- (“whole, entire”), from *pénkʷe (“whole hand; five (fingers)”). In this case cognate to Sanskrit पञ्च (pañca, “spread out”), Sanskrit प्रपञ्चन (prapañcana, “copiousness”).
Ancient etymologists explained it as a contraction of *cōiūnctus, making it a doublet of coniūnctus (“conjoined, connected”); this is today rejected.

(Classical Latin) IPA^(key): /ˈkuːnk.tus/, or IPA^(key): /ˈkunk.tus/,
(modern Italianate Ecclesiastical) IPA^(key): /ˈkunk.tus/,
Note: the length of the root vowel is uncertain; length is regular before /nkt/, but this depends on whether the syncope preceded the lenthening. This is further complicated by the existence in Latin of an Osthoff's law-like tendency to shorten vowels followed by nasal+stop consonants. Compare the same uncertainity in the unrelated verb cū̆nctor, likely influenced by the adjective via false-etymological derivation or vice versa.

cū̆nctus (feminine cū̆ncta, neuter cū̆nctum); first/second-declension adjective

collectively, all together; the whole, entire
Synonyms: (in the plural) omnis, (in the singular) tōtus
- 29 BCE – 19 BCE, Virgil, Aeneid 1.518:
  cūnctīs nam lēctī nāvibus ībant
  for chosen men from all the ships went forth

Case / Gender	Masculine	Feminine	Neuter	Masculine	Feminine	Neuter
Number	Singular			Plural
Nominative	cū̆nctus	cū̆ncta	cū̆nctum	cū̆nctī	cū̆nctae	cū̆ncta
Genitive	cū̆nctī	cū̆nctae	cū̆nctī	cū̆nctōrum	cū̆nctārum	cū̆nctōrum
Dative	cū̆nctō	cū̆nctae	cū̆nctō	cū̆nctīs
Accusative	cū̆nctum	cū̆nctam	cū̆nctum	cū̆nctōs	cū̆nctās	cū̆ncta
Ablative	cū̆nctō	cū̆nctā	cū̆nctō	cū̆nctīs
Vocative	cū̆ncte	cū̆ncta	cū̆nctum	cū̆nctī	cū̆nctae	cū̆ncta

^ Pokorny, Julius (1959) Indogermanisches etymologisches Wörterbuch [Indo-European Etymological Dictionary] (in German), volume 2, Bern, München: Francke Verlag, page 538
^ De Vaan, Michiel (2008) “cunctus”, in Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill, →ISBN, page 154
^ Ernout, Alfred, Meillet, Antoine (1985) “cunctus”, in Dictionnaire étymologique de la langue latine: histoire des mots‎ (in French), 4th edition, with additions and corrections of Jacques André, Paris: Klincksieck, published 2001, page 157
^ Sihler, Andrew L. (1995) New Comparative Grammar of Greek and Latin, Oxford, New York: Oxford University Press, →ISBN, pages 145, 300, 437