1) This phrase refers to any event where innocent person(s) were taken quietly and unassumingly to their deaths without the people who know them discovering about it until after it happened.

2) It is also a short story by Roald Dahl, the author of charlie and the chocolate factory.
"The Jews were lead to the showers like lambs to the slaughter during WWII"

"At Gethsemane, Christ knew he had to be led like a lamb to the sluaghter"
by Gumba Gumba March 10, 2004
A person accepting punishment/harm with dignity, without crying out, as Jesus was during his crucifixion.
He was led as a lamb to the slaughter. And as a sheep is silent before the shearers, he did not open his mouth.
by EJL March 31, 2004
the definition of the phrase lambs to the slaughter is that you play among us without knowing there is an impostor
he went around and did his tasks not suspecting his death to be around the corner

lambs to the slaughter
by dudesup123 October 14, 2020
to o something not knowing something bad is going to happen
hey bub your going to wrestle like a lamb to slaughter
by i m not jeff September 28, 2017
Lamb to slaughter line refers an unsatisfying or dead-end job that seems like it would lead you to your death.
I have to get home before morning because I have to go my lamb to slaughter line.
by spen53 March 29, 2018