N: naquadah, narim, nox, nirrti...

[Vern]

Naquadah
Stargates are made of the element Naquadah (sometimes transliterated from the original language as Naquada), a quartzite metal not found on Earth. A teleportational wormhole is generated when charged neutrinos are applied to Naquadah, the only known element that absorbs and energizes with neutrinos. This forms a stable, artificial wormhole that connects to another stargate. The derivative Naquadria is a powerful yet unstable fuel source; prolonged exposure to its radiation can cause mental disorders.


Narim


Nox
Small, peaceful, fairylike people occupying a planet previously thought to be uninhabited, the Nox can make things invisible and resurrect the dead. First contact was in season one's "The Nox". Making up one of the races in the great alliance of four, most of them live in a large floating city.


Nirrti

[CaptainHaz]

Novak, Dr. Lindsay

An engineer who is part of the crew of the Prometheus. She previously declined an offer to go on the original Atlantis expedition. She gets hiccups when she is nervous.

[NIKIN]

Naquadria

An unstable form of Naquadah created artificially on Langara, Jonas Quinn's home world. It was created from normal naquadah by a system lord in a lab, however much of the naquadah veins below Kelowna were also efected. After the veins went dry, more naquadriah was created by the test of the naquadriah bomb; the result of this naquadria breaking down almost caused the planet to be destroyed although it was prevented by SG1.

Gives off radiation that prolonged exposure to causes mental illness such as schitzofrinia or even death, such as happened to Dr. Daniel Jackson (Meridian)

In an attempt to create a super-powerful weapon, Anubis invaded Langara but was stopped by SG1 shortly after they had destroyed his most recent asset (the combined power of the "eyes of the Gods")

[Vern]

Need (episode)
While exploring planet P3R 636, O'Neill and the SG1 team come across what appears to be a troop of Jaffa warriors and ceremonial priests delivering Naquadah, an element treasured by the Goa'uld, through the Stargate.

New Ground (episode)
The SG-1 team travels to the planet Bedrosia where, unbeknownst to them, the planet's two cultures have been at war over their opposed beliefs regarding the Stargate.

Nemesis (episode)
While preparing for a week of leave, O'Neill is engulfed in a white glow and disappears.

New Order (episode)
When Carter and Teal'c fly to the Asgard world of Hala to try and revive O'Neill. Replicators attack them and Carter is taken prisoner. Meanwhile, Dr. Weir and Daniel Jackson attempt to negotiate a treaty with Goa'uld System Lords who wish to unite against a common enemy.
Then in part two the Goa'uld send a mothership to Earth demanding that it prove its superior defences. Dr Weir is deep in negotiations with the Goa'uld while Daniel and the still unconscious O'Neill are beamed aboard Thor's ship where Thor tries to access the knowledge of the Ancients.

[Vern]

Nightwalkers (episode)
Carter, Teal'c and Jonas investigate the death of a scientist with connections to the Goa'uld, and find a small town whose inhabitants are part of a secret experiment.