Where does “amasiĝi” come from?

amasiĝi (Esperanto) comes from Esperanto amaso, from French amas, from Italian ammasso, from Italian ammassare, from Latin amassāre, from Latin massa, from Ancient Greek μᾶζα, from Ancient Greek μάσσω — to knead, stroke.

amasiĝi (Esperanto): to accumulate, gather, pile up; to gather

Definitions

to accumulate, gather, pile up; to gather

Ancestry of “amasiĝi”, step by step

Step	Language	Word	Meaning
1	Esperanto	amaso	mass large quantity
2	French	amas	pile, heap; cluster
3	Italian	ammasso	pile, heap, mass; stockpile; thicket
4	Italian	ammassare	to pile up, accumulate, amass, hoard; to pack
5	Latin	amassāre	—
6	Latin	massa	mass, bulk; load, burden; dough
7	Ancient Greek	μᾶζα	barley-bread or cake
8	Ancient Greek	μάσσω	to handle, work with my hands, knead; to wipe
9	Proto-Indo-European	mh₂ǵyéti	—
10	Proto-Indo-European	meh₂ǵ-	to knead, stroke

Every word from Proto-Indo-European meh₂ǵ- →Every word from Proto-Indo-European mh₂ǵyéti →Every word from Ancient Greek μάσσω →