Common terms and abbreviations.

HAWT	Horizontal Axis Wind Turbine
VAWT	Vertical Axis Wind Turbine
TSR	See_ Tip Speed Ratio
Tip Speed Ratio	The speed of the propeller tip compared to the winds speed that drives it. _ More
A of A	See_ Angle of Attack
Angle of Attack	Angle between the relative wind and the prop blade _ More
Relative wind	The angle of the wind relative to a moving surface(plane of a rotating prop) _ More
Apparent wind	See_ Relative Wind
Blade Angle	Angle between the blade and the plane at 90deg to the prop shaft. (also called Pitch) _ LINK
Pitch	Angle between the blade and the plane at 90deg to the prop shaft. (also called Blade Angle) _ More
cct	Circuit
MPP	Maximum Power Point. The point in the Volt Amp ratio where maximum power is transferable.
MPPT	See_ Maximum Power Point Tracking (Wind).
Maximum Power Point Tracking (Wind)	An electronic device that adjusts power levels and their Volt Amp ratio to cause the maximum transfer of wind power to the battery. MPPT(Solar) is less complex and robust.
flux	Magnetic force. The path/shape of this force is the magnetic field.
PMG	Permanent Magnet Generator.
pole	Magnetic Pole eg. North/South also the protruding laminated finger the coils are wound around.
core	Material inside a coil to concentrate magnetic flux. Laminates of steel and air most common, ferrite rare.
cogging	Magnetic attraction between the rotor magnets and the steel core laminations that resists initial starting forces.
clogging	Frustrated bashing of wind generator with a Dutch wooden shoe. Actually any piece of wood or solid item at hand will do. (joke)
magic smoke	The stuff that makes anything electrical work - so long as it stays within the wire. (joke)
SOC	State of Charge of a battery.
Furl	The deliberate movement of the prop from full exposure to the wind to the minimal side on/in-line exposure to make the prop slow or stop. _ More
Yaw	Rotational movement about a vertical axis(mast). This movement allows the prop to point at the wind when it changes direction.
Yaw Bearing	The mast bearings that allows yaw movement.
Star	An AC generator phase wiring arrangement giving a higher voltage with lower current output for a given RPM. Also called wye in the USA.
wye	See_ Star.
Delta	An AC generator phase wiring arrangement giving a lower voltage for a higher current output for a given RPM.
Inde	See_ Independent. _ More
Independent	Configuration that independently rectifies each phase before series/paralleling to give final DC output. (also called Jerry Rig on the USA windmill forums). _ More
Jerry Rig	A USA forum term for independently rectifying each coil output before combining for total DC output. See_ Independent.
Swept Area	The area covered by the rotating propeller on a HAWT or rotor on a VAWT. On a VAWT the cubic nature is considered beyond the mere wind frontage area as in the case of the HAWT.
Shunt Regulator	Battery protection device, fitted across a battery for turning on a dump load also across the battery and so prevent overcharging.
Controller	A term often used for either a Shunt Regulator or Diversion Controller.
Diversion Controller	Battery protection device fitted between the generator and the battery to divert excess power from the battery to a dump load and so prevent overcharging the battery.
Regulator	See_ Shunt Regulator
EMF	Electro Motive Force. The unit of measurement is the Volt.
Back EMF Braking	A deliberate short circuiting of the generators output to cause maximum load and so (usually) stop it turning.
Buck Converter	Electronic arrangement that converts/transforms the Volt Amp relationship of power. It reduces The Voltage and increases the current for a final reduced power due to conversion losses.
Boost Converter	Electronic arrangement that converts/transforms the Volt Amp relationship of power. It increases the Voltage and decreases the current for a final reduced power due to conversion losses.
Stall	The state of a propeller when the power required (generator loading) exceeds the props driving force (derived from the wind).
MMF	See_ Magnetomotive force
Magnetomotive force	Also known as magnetic potential, is the property of certain substances or phenomena that gives rise to magnetic fields. The unit of measurement is the AmpTurn (AT).
Dump Load	Any load, but usually resistive, that dissipates the excess power that would otherwise overcharge a battery. Control of the dump load is by a Shunt Regulator or Diversion Controller.
VFD	See_ Variable Frequency Drive
Variable Frequency Drive	Is an electronic device for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor.
Islanding	A small section of a power grid that is still 'LIVE' despite the overall grid shut down. Caused by a back-yarder's generator illegally feeding into the grid. **DEADLY** .

Special thanks to Gill for putting most of these terms together