May as well list what I do know, to help start it off. Not alphabetical, it came out of my head like this!
Beam: What's being circulated in the LHC or attached accelerators at high speeds (nearly the speed of light) and (relatively) high energy. This can be protons, ions or possibly something more exotic.
Beam 1/B1: Clockwise beam, usually shown in blue. Joins the LHC from the SPS at Point 2 (TI2).
Beam 2/B2: Anticlockwise beam, usually shown in red. Joins the LHC from the SPS at Point 8 (TI8).
Point/Octant [x]: The LHC has 8 "points" around it. They are as such:
Point 1: ATLAS
Point 2: ALICE, Beam 1 Entry
Point 3: Beam Cleaning (Momentum)
Point 4: RF (Radio Frequency, meaning..?)
Point 5: CMS
Point 6: Dump
Point 7: Beam Cleaning (Betatron)
Point 8: LHCb, Beam 2 Entry
Sector [xy]: The area between 2 Points. Sector 12 is between ATLAS and ALICE, Sector 23 between ALICE and Beam Cleaning, etc.
Dump: Disposing of the beams after use. Because of their high energy nature, they must be dealt with carefully to prevent irradiation of staff and damage to equipment. Don't think they're weak because they're small - the beams can punch a hole through solid metal! See the Collimator link below/on Outreach for pictures of this.
See: http://lhc-machine-outreach.web.cern.ch ... m-dump.htm
Magnets: These are used to steer, contain and focus the beam. This is due to the fact that a charged particle within a magentic field is deflected. The LHC has over 1200 of these. See: http://lhc-machine-outreach.web.cern.ch ... agnets.htm
Collimator: A Device used to catch stray particles from the beam, stopping them from damaging equipment or irradiating staff. See: Dump, http://lhc-collimation-project.web.cern ... uction.htm
Cryo/Cryogenics: The LHC must be kept at a very cold temperature in order to operate - a few degrees above absolute zero. Most notably, the superconductors used to power the magnets require very cold temperatures. See: http://lhc-machine-outreach.web.cern.ch ... genics.htm
LIN/LINAC: Linear Accelerator. First stage used to accelerate protons and ions. See: http://lhcportal.com/Forum/viewtopic.php?p=157#p157
PS or Pre-Injector: Proton Synchrotron. Second stage used to accelerate protons, third for ions. A former CERN accelerator like the LHC in its own right, now 50 years old, and part of the LHC complex.
SPS or Injector: Super Proton Synchrotron. Final stage of acceleration for protons and ions before the LHC. A former CERN accelerator like the LHC in its own right, now part of the LHC complex.
LEP: Large Electron-Positon collider. A former CERN accelerator for Leptons (a Lepton accelerator called LEP, fancy that!) such as electrons and positrons, quite obviously. This was taken out of use in 2000, and the tunnels of the LEP were re-used for the LHC.
LEIR: Low Energy Ion Ring. Secondary Ion Acceleration.
Injection/Injecting: Putting various types of particles into the LHC - creating a beam.
Luminosity: A measure of how many particles are going through an area per second. Used to measure how many particles are in a beam (?), units are cm-2 s-1 (Particles per centimeter squared per second).
Intensity: A measure of the power of the beam (?)
Electron Volt/eV/MeV/GeV/TeV: Used to measure how much energy the particles in the accelerator. A very small amount of energy (lifting an apple 1 metre would require 6.25 billion billion eV!)
To indicate many eV, SI prefixes may be used. The LHC commonly uses:
MeV - Mega Electron Volt - 1,000,000 eV - 1e6 eV
GeV - Giga Electron Volt - 1,000,000,000 eV - 1e9 eV - 1,000 MeV
TeV - Tera Electron Volt - 1,000,000,000,000 eV - 1e12 eV - 1,000 GeV