A term used, mainly in automotive circles, to describe torque (turning force) produced at low engine speed (low RPM's). A car with a lot of low-end torque will likely have its torque peak at a very low RPM level.
Cars with a lot of low-end torque accelerate very quickly from a standstill or from a slow speed. However, performance at higher speeds suffer, because at high speeds, the engine is operating at a high RPM level beyond the torque band of the engine. Therefore, not much force is being applied at high speeds. This effectively limits the top speed of a car with low-end torque.
The Camaros of the late 70's are an extremely good example of cars with low end torque. Take, for example, the 1978 Camaro Z28. It's peak torque is 280 ft-lbs at 2400 RPM. 2400 RPM is extremely low compared to the cars of today, which have their torque peak at around 4000-6000 RPM. As a consequence, the Camaro, a 3600 pound car, can acclerate from zero to sixty MPH in a bit over 7 seconds with an engine producing only 185 horsepower. This is absolutely amazing, considering the low horsepower and high weight of the car. However, the top speed of the 1978 Camaro is a mediocre 125 mph.