Where does “glattire” come from?

glattire (Medieval Latin) comes from Latin glattio, from Latin latro, from Ancient Greek λάτρον, from Proto-Indo-European leh₂t- — to grant, to possess.

Ancestry of “glattire”, step by step

Step	Language	Word	Meaning
1	Latin	glattio	I howl
2	Latin	latro	mercenary; highwayman; brigand, bandit; robber;...
3	Ancient Greek	λάτρον	payment; pay, hire
4	Proto-Indo-European	leh₂t-	to grant, to possess

Every word from Proto-Indo-European leh₂t- →Every word from Ancient Greek λάτρον →Every word from Latin latro →