Where does “ius iurandum” come from?

ius iurandum (Latin) comes from Latin iūs, from Latin dīcō, from Latin -tiō, from Latin dissertātiō, from Latin dissertus, from Latin disserere, from Latin dis-, from Latin calceus — small stone, pebble; gravel, rubble.

ius iurandum (Latin): an oath

Definitions

an oath

Ancestry of “ius iurandum”, step by step

ius iurandum traces back through two separate lines of ancestry.

via Latin iūs

Step	Language	Word	Meaning
1	Latin	iūs	law, right
2	Latin	dīcō	to say, talk, speak, utter, mention
3	Latin	-tiō	tion, -ation, -ing
4	Latin	dissertātiō	(spoken) dissertation, discourse, disquisition
5	Latin	dissertus	arranged, disposed; explained
6	Latin	disserere	second-person singular future passive indicative...
7	Latin	dis-	asunder, apart, in two; reversal, removal;...
8	Latin	calceus	shoe
9	Latin	calx	limestone; chalk; the finish line
10	Ancient Greek	χάλιξ	small stone, pebble; gravel, rubble

via Latin iurandus

Step	Language	Word	Meaning
1	Latin	iurandus	which is to be vowed
2	Latin	iūrō	to confirm formally, to pronounce enforceably, to swear, to vow, to take an oath
3	Old Latin	iovesō	—

Every word from Ancient Greek χάλιξ →Every word from Latin -tiō →Every word from Latin dis- →