nth root : If the power is 1/2 then we call it as square root, if the exponent is 1/3 then we call it as cube root but if the exponent is other than 1/2 and 1/3 then we call it as 'nth root'. For example: 2^{1/4} then it is 4th root of 2.

Natural logarithm : It is a logarithm with base 'e'. The value of e = 2.718281828.

Natural Number : The whole numbers from 1 upwards: 1, 2, 3, and so on ...

Negative : Less than zero. A negative number is written with a minus sign in front ( -5).

Negative exponent : When the power of any number is negative then it is called negative exponent. For example : 5^{-2}.

Negation: For any given statement p , its negation is the statement , ~ p (not p ) whose truth value is the opposite of the truth value of p .

Net: A two dimensional pattern consisting of polygons which can be folded to form a polyhedron.

N-gon: A polygon with n sides.

Nonagon: A polygon with 9 sides.

Non-collinear points: Three or more points that do not lie on the same line.

Non- coplanar points: Four or more points that do not lie on the same plane.

Non-Euclidean geometry: A geometry that contains an axiom which is equivalent to the negation of the Euclidean parallel postulate.

Non-Parallel: Intersecting lines.

Not equal : Opposite of equal and it is denoted by ≠

Number line : A line with numbers placed in their correct position. Number Pattern : A list of numbers that follow a certain sequence or pattern.

Number Sense : A person's ability to use and understand numbers.

Number system : Number system is categorized into different types of numbers such as whole numbers, rational numbers, integers etc.

Numeral : A symbol or name that stands for a number.