frequency vs relative frequency

frequency and relative frequency both are nouns.

Word	Noun	Adjective	Verb	Adverb
frequency	Yes	No	No	No
relative frequency	Yes	No	No	No

As nouns, frequency and relative frequency are synonyms defined as:

frequency and relative frequency: the ratio of the number of observations in a statistical category to the total number of observations

frequency (noun)	relative frequency (noun)
the number of observations in a given statistical category	the ratio of the number of observations in a statistical category to the total number of observations
the ratio of the number of observations in a statistical category to the total number of observations
the number of occurrences within a given time period