running headline vs running head

running headline and running head both are nouns.

Word	Noun	Adjective	Verb	Adverb
running headline	Yes	No	No	No
running head	Yes	No	No	No

As nouns, running headline and running head are synonyms defined as:

running headline and running head: a heading printed at the top of every page (or every other page) of a book

running headline (noun)	running head (noun)
a heading printed at the top of every page (or every other page) of a book	a heading printed at the top of every page (or every other page) of a book