Napier's bones 

nounw:John Napier, Napier's bonesplural

(arithmetic) A set of numbered rods used for multiplication and division (see the Wikipedia article for a fuller explanation).
 
nappe 

noun
 the profile of a body of water flowing over an obstruction in a vertical drop

(mathematics) either of the two parts of a double cone

(geology) a sheetlike mass of rock that has been carried from its original position

(context, hydraulics) Nappe, the underside of which is not in contact with the overflow structure and is at ambient atmospheric pressure.

natural number 

noun

(mathematics) a member of the set of natural numbers. The definition of exactly what is a natural number seems to vary, depending on if zero is included or not. Thus, by the term , one may refer to a positive integer (set of 1,2,3,...) or a nonnegative integer (set of 0,1,2,3,....

neighborhood 

noun
 The nearby area, particularly when referring to home.
We have just moved to a pleasant
 and by extension, it's inhabitants.
The fire alarmed the neighborhood.

(uncountable) The quality of proximity.
 "Then the prison and the palace were in awful neighbourhood." — w:Edward BulwerLytton, 1st Baron Lytton, Lord Lytton.

(obsolete) The disposition becoming a neighbor; neighborly kindness or good will.

nested 

verb

(past of, nest)

Net 

proper nounthe Net
(computing) The Internet.

node 

noun (pluralnodes)
 A knot, a knob; a protuberance; a swelling.

(Astronomy) The point where the orbit of a planet, as viewed from the sun, intersects the ecliptic. The ascending and descending nodes refer respetively to the points where the planet moves from S to N and N to S. The respective symbols are â˜Š and â˜‹.
 The joint of a stem, or the part where a leaf or several leaves are inserted.
 A hole in the gnomon of a dial, through which passes the ray of light which marks the hour of the day, the parallels of the sun's declination, his place in the ecliptic, etc.

(geometry) The point at which a curve crosses itself, being a double point of the curve. See Crunode, and Acnode.
 The point at which the lines of a funicular machine meet from different angular directions;  called also knot.
 The knot, intrigue, or plot of a piece.
 A hard concretion or incrustation which forms upon bones attacked with rheumatism, gout, or syphilis; sometimes also, a swelling in the neighborhood of a joint.
 One of the fixed points of a sonorous string, when it vibrates by aliquot parts, and produces the harmonic tones; nodal line or point.
 A swelling.

(graphtheory) A vertex of a graph.

(computing_theory) (context, computer networking) A vertex or a leaf in a graph of a network; a computer or other device attached to a network

nomogram 

noun (pluralnomograms)

(mathematics) A diagram in which the relationship between three variables is represented by a straight line or curve for each variable; the value of the third variable corresponding to particular values of the first two is obtained by drawing a straight line through the points on the first two curves that represent particular values of the first two variables and noting the point at which the line intersects the third line or curve.

nonagon 

noun

(geometry) A polygon with nine sides and nine angles.

nonEuclidean geometry 

noun

(geometry) Any system of geometry not based on the set of axioms of Euclidean geometry, which is based on the threedimensional space of common experience.

nonstandard 

adjective
 Not standard.

(linguistics) Not conforming to the language used by the educated sections of a society.

ntuple 

noun 
number 

noun

(countable) An abstract entity used to describe quantity.

(countable) A symbol for a nonnegative integer; a numeral.

(countable) (mathematics) A member of one of several classes: natural numbers,integers, rational numbers, real numbers, complex numbers, quaternions.
The equation <math>e^{i\pi}+1=0</math> includes the most important numbers: 1, 0, <math>\pi</math>, <math>i</math>, and <math>e</math>.
(Followed by a numeral; used attributive) show, Showing the rank of something in a list or sequence. Abbreviations: No or No., no or no. (in each case, sometimes written with a superscript "o", like NÂº or &
 x2116;). The symbol "
 " is also used in this manner.
Horse 5 won the race.
 quantity, Quantity.
Any of people can be reading from a given repository at a time

(grammar) Of a word or phrase, the state of being singular, dual or plural, shown by inflection.

(countable) A performance; especially, a single song or song and dance routine within a larger show.
For his second , he sang "The Moon Shines Bright".
verb

(transitive) To label (items) with numbers; to assign numbers to (items).
Number the baskets so that we can find them easily.

(intransitive) To total or count; to amount to.
I don"t know how many books are in the library, but they must in the thousands.
adjective

(comparative of, numb)

number theory 

noun (uncountable)

(mathematics) The branch of pure mathematics concerned with the properties of integers.

Factorization has driven many great discoveries in .

numeral 

noun
 A word or symbol representing a number.

The word "fifteen", the Arabic "15", and the Roman "XV" are all numerals representing the number fifteen.

numerator 

noun (plural:numerators)

(arithmetic) The number or expression written above the line in a fraction.
 An enumerator; someone who counts things.

numerical 

adjective of or pertaining to numbers

numerical analysis 

noun (uncountable)

(mathematics) the study of algorithms to solve problems in mathematics on continuous sets of numbers (such as the real numbers)

