cunctus.

Uncertain. Proposals include: * From concitus by syncope per Pokorny (1959), accepted by De Vaan (2008) with some reservations. Ernout and Meillet (1985) reject this etymology, and also reject the ancient etymology from co(n)iūnctus. * 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 [script needed] (pa-an-kur, “family, relations”), as well as the middle part of Ancient Greek ᾰ̔́πᾰξ (hắpăx, “singly”). The Latin form would then show the same /p – kʷ > kʷ – kʷ/ assimilation as in quīnque. De Vaan rejects this etymology, saying that the Hittite term cannot be cognate with Latin cūnctus due to the genitive singular form 𒉺𒀭𒅗𒉿𒀸 (/⁠pa-an-ka-wa-aš⁠/), and that it is more likely related to Sanskrit ब॒हु (bahú). * From Proto-Indo-European *ponkʷ-to- (“whole, entire”), from *pénkʷe (“whole hand; five (fingers)”). In this case cognate to Sanskrit पञ्च॑ (páñca, “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.