cotangent vs circular function

cotangent and circular function both are nouns.

Word	Noun	Adjective	Verb	Adverb
cotangent	Yes	No	No	No
circular function	Yes	No	No	No

As nouns, circular function is a hypernym of cotangent; that is, circular function is a word with a broader meaning than cotangent:

cotangent: ratio of the adjacent to the opposite side of a right-angled triangle
circular function: function of an angle expressed as a ratio of the length of the sides of right-angled triangle containing the angle

Other hypernyms of cotangent include trigonometric function.

cotangent (noun)	circular function (noun)
ratio of the adjacent to the opposite side of a right-angled triangle	function of an angle expressed as a ratio of the length of the sides of right-angled triangle containing the angle