indictment vs bill of indictment

indictment and bill of indictment both are nouns.

Word	Noun	Adjective	Verb	Adverb
indictment	Yes	No	No	No
bill of indictment	Yes	No	No	No

As nouns, indictment and bill of indictment are synonyms defined as:

indictment and bill of indictment: a formal document written for a prosecuting attorney charging a person with some offense

indictment (noun)	bill of indictment (noun)
a formal document written for a prosecuting attorney charging a person with some offense	a formal document written for a prosecuting attorney charging a person with some offense
an accusation of wrongdoing