Where does “veintiúnico” come from?

veintiúnico (Spanish) comes from Spanish veinte, from Old Spanish veynte, from Latin vīgintī, from Latin quīnque, from Proto-Italic kʷenkʷe, from Proto-Indo-European pénkʷe — five.

veintiúnico (Spanish): unique, singular

Definitions

unique, singular

Ancestry of “veintiúnico”, step by step

veintiúnico traces back through 3 separate lines of ancestry.

via Spanish veinte

Step	Language	Word	Meaning
1	Spanish	veinte	twenty
2	Old Spanish	veynte	twenty
3	Latin	vīgintī	twenty
4	Latin	quīnque	five; 5
5	Proto-Italic	kʷenkʷe	five
6	Proto-Indo-European	pénkʷe	five

via Spanish único

Step	Language	Word	Meaning
1	Spanish	único	only; single; sole; unique, one-of-a-kind;...
2	Latin	ūnicus	only, sole, single
3	Latin	ūnus	one, single
4	Old Latin	oinos	one
5	Proto-Italic	oinos	cardinal number 1 Previous: n/a Next: *duō;...
6	Proto-Indo-European	óynos	one; single

via Spanish y

Step	Language	Word	Meaning
1	Spanish	y	and; plus, and; well
2	Old Spanish	e	and
3	Latin	et	and; plus; though, even if
4	Proto-Indo-European	éti	beyond; over
5	Proto-Indo-European	h₁é	and, then
6	Proto-Indo-European	ǵʰe	Postpositional intensifying particle: indeed, at any rate, in fact

Every word from Proto-Indo-European pénkʷe →Every word from Proto-Italic kʷenkʷe →Every word from Latin quīnque →