A general term used was liquidation.The term used for the large-scale killing of the Jews was the Final Solution - short for the Final Solution of Jewish Question.
The Final Solution was the name of the plan. The Allies knew of the final solution through intel, but thought it was a military plan, not plans for the Holocaust.
Solution is a noun and final is an adjective and the Final Solution is a noun phrase or, arguably, a proper noun.
Children were treated good in the final solution
the ghettos came before the final solution
The Final Solution went on for about three years.
The Final Solution was the plan to rid of Europe's Jews.
The Final Solution (of the Jewish question).
'Resettlement' was a euphemism for being deported to the ghettos.
Resettlement Administration was created in 1935.
"The Final Solution." Or "Final Solution." Often referred to in Nazi documents as "The Final Solution to the Jewish Question". Note that Hitler never actually came up with a specific plan - his subordinates (led by Himler and Heydrich) gathered together a committee to devise the actual plan, at the direction of Hitler.
final solution = Endlösung