LFE audio channel is different from subwoofer output.

Subwoofers come with multichannel audio systems in which directional speakers usually can't cover the lower range of audio frequencies. They are responsible for bass content from all channels, and get it from software or hardware crossover filter which is independent from specific input formats. Placement of low frequency speaker does not matter much because of human perception.

LFE track is an additional effects channel for movie theaters and similar amusement rides in which audio system plays low frequencies from other channels just fine. Dedicated LFE emitter then adds rattling and other wub-wub effects without overloading audio speakers with all that extra energy. Movies that lack car chases and explosions routinely have completely silent LFE tracks.

So it's essentially a bass shaker track?

Today, it seems to be it. The article does mention that historically the limits of transmission and playback systems were the reason for introduction of independent channel for lowest frequencies (instead of mixing it into main audio channels).

https://en.wikipedia.org/wiki/Low-frequency_effects

LFE is an industry standard term for the subwoofer channel. It's the ".1" in "5.1","6.1","7.1" etc

LFE is usually a bass shaker which is a subwoofer but it moves a weight instead of a cone, so you get vibrations in your seat. It stimulates movement to your body somewhat, I use two for my sim racing rig, one under my seat to inform me of the car dynamics and immersive feeling, one under my pedals to inform me when ABS is active and when my tires are spinning.

LFE can mean "bass shaker", but it's an industry-standard term invented by Dolby that effectively means "between 3 and 120hz", which usually means "subwoofer".

These days crossover points are very configurable. Most bass shakers are rated for use between 20hz and 200hz.

Low frequency energy, I assume. Ie bass. Your subwoofer or „bottoms“ if you have several.