1 (wiktionary) 2 (vi.wikipedia) 3 (en.wikipedia) 4 (glosbe)

Core Words Familarize yourself with the 'core words'.
Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
Etymology Explore the origin of the 'core words'.

{n}	sacrifice	(something sacrificed)	Opfer {n}
{v}	sacrifice	(to give away something valuable in order to gain something else of value)	opfern
{v}	sacrifice	(to offer as a gift to a deity)	opfern