My first guess would have been "Low Voltage Dsomething Tsomething."

So how do Linear Variable Displacemtent Transformers work? Does a movable ferrous core slide in and out of a fixed transformer, or does a movable secondary slide in and out of a fixed primary? And if it's the latter case, how do they keep it linear with the fringe field effect? Finally, what do you use them for? Obviously they'd make good position sensors for feedback control, but do you use them for anything else?