1. [n]  the 14th letter of the Roman alphabet
2. [n]  (of a solution) concentration expressed in gram equivalents of solute per liter
3. [n]  a unit of force equal to the force that imparts an acceleration of 1 m/sec/sec to a mass of 1 kilogram; equal to 100,000 dynes
4. [n]  the cardinal compass point that is at 0 or 360 degrees
5. [n]  a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues

.N
.N

more details ...

1. The religion, or doctrines and precepts, of Mohammed,
   contained in the Koran; Islamism.
   

2. \N\ ([e^]n),
   the fourteenth letter of English alphabet, is a vocal
   consonent, and, in allusion to its mode of formation, is
   called the dentinasal or linguanasal consonent. Its commoner
   sound is that heard in ran, done; but when immediately
   followed in the same word by the sound of g hard or k (as in
   single, sink, conquer), it usually represents the same sound
   as the digraph ng in sing, bring, etc. This is a simple but
   related sound, and is called the gutturo-nasal consonent. See
   {Guide to Pronunciation}, [sect][sect] 243-246.
   Note: The letter N came into English through the Latin and
         Greek from the Ph[oe]nician, which probably derived it
         from the Egyptian as the ultimate origin. It is
         etymologically most closely related to M. See {M}.
   

3. \N\, n. (Print.)
   A measure of space equal to half an M (or em); an en.
   

4. One who, or that which, tranquilizes.
   

/N/ quant. 1. A large and indeterminate number of objects: "There were N bugs in that crock!" Also used in its original sense of a variable name: "This crock has N bugs, as N goes to infinity." (The true number of bugs is always at least N + 1; see Lubarsky's Law of Cybernetic Entomology.)

2. A variable whose value is inherited from the current context. For example, when a meal is being ordered at a restaurant, N may be understood to mean however many people there are at the table. From the remark "We'd like to order N wonton soups and a family dinner for N - 1" you can deduce that one person at the table wants to eat only soup, even though you don't know how many people there are.

3. "Nth": The ordinal counterpart of N, senses 1 and 2. "Now for the Nth and last time..." In the specific context "Nth-year grad student", N is generally assumed to be at least 4, and is usually 5 or more (see tenured graduate student). See also random numbers, two-to-the-N.

[Jargon File]