Where does “elkészült” come from?

elkészült (Hungarian) comes from Hungarian elkészül, from Hungarian el-, from Hungarian -ső, from Hungarian -s — Added to a noun to form an adjective meaning...

Ancestry of “elkészült”, step by step

Step	Language	Word	Meaning
1	Hungarian	elkészül	to finish, to reach completion, to be ready
2	Hungarian	el-	indicates actions whose direction is pointing...
3	Hungarian	-ső	Added to a noun or a stem to form an adjective
4	Hungarian	-s	Added to a noun to form an adjective meaning...

Every word from Hungarian -s →Every word from Hungarian el- →Every word from Hungarian -ső →