It is an adjective.
Meaning : taking words in their usual or primary sense without metaphor or allegory.This means we use the actual meaning i.e exact, avoiding exaggeration or any indirect meaning or inaccuracy.
Root of the word: litera = letter
literalness - noun
Synonyms : honest, accurate, exact, unembroidered, unembellished, plain,verbal,plain,veracious,verbatium
Antonyms : figurative
1)Literal translations may sound very bland.
2)She gave the literal description of what has happened.
3)He made a literal error in his work which had cost him a month's salary.