terror vs holy terror

terror and holy terror both are nouns.

Word	Noun	Adjective	Verb	Adverb
terror	Yes	No	No	No
holy terror	Yes	No	No	No

As nouns, terror and holy terror are synonyms defined as:

Other synonyms of terror include brat, little terror.

terror (noun)	holy terror (noun)
the use of extreme fear in order to coerce people (especially for political reasons)	a very troublesome child
an overwhelming feeling of fear and anxiety
a very troublesome child
a person who inspires fear or dread