Where does “mallachtú” come from?

mallachtú (Irish) comes from Irish mallachtaigh, from Irish mallacht, from Middle Irish mallacht, from Old Irish maldacht, from Latin maledictiō, from Latin maledīcō, from Latin dīcō, from Latin -tiō — small stone, pebble; gravel, rubble.

Ancestry of “mallachtú”, step by step

Step	Language	Word	Meaning
1	Irish	mallachtaigh	Synonym of mallaigh; vocative singular masculine...
2	Irish	mallacht	curse, malediction
3	Middle Irish	mallacht	curse, malediction
4	Old Irish	maldacht	curse
5	Latin	maledictiō	curse, evil speech
6	Latin	maledīcō	to slander, speak ill of
7	Latin	dīcō	to say, talk, speak, utter, mention
8	Latin	-tiō	tion, -ation, -ing
9	Latin	dissertātiō	(spoken) dissertation, discourse, disquisition
10	Latin	dissertus	arranged, disposed; explained
11	Latin	disserere	second-person singular future passive indicative...
12	Latin	dis-	asunder, apart, in two; reversal, removal;...
13	Latin	calceus	shoe
14	Latin	calx	limestone; chalk; the finish line
15	Ancient Greek	χάλιξ	small stone, pebble; gravel, rubble

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