highly educated; having extensive information or understanding; "an enlightened public"; "knowing instructors"; "a knowledgeable critic"; "a knowledgeable audience"
an officer holding a commissioned rank in the United States Navy or the United States Coast Guard; below lieutenant commander and above lieutenant junior grade
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 number of occurrences within a given time period; "the frequency of modulation was 40 cycles per second"; "the frequency of his seizures increased as he grew older"