twin bill vs doubleheader

twin bill and doubleheader both are nouns.

Word	Noun	Adjective	Verb	Adverb
twin bill	Yes	No	No	No
doubleheader	Yes	No	No	No

As nouns, twin bill and doubleheader are synonyms defined as:

twin bill and doubleheader: two games instead of one (especially in baseball when the same two teams play two games on the same day)

Other synonyms of twin bill include double feature.

twin bill (noun)	doubleheader (noun)
two games instead of one (especially in baseball when the same two teams play two games on the same day)	two games instead of one (especially in baseball when the same two teams play two games on the same day)