Impedimenta is used to prevent the target from reaching the caster. Usually, Impedimenta causes the target to trip or fall backwards, as well as stopping in place.
Imperio is an Unforgivable Curse that causes the target to be under the control of the caster. Therefore, the target must do whatever the caster's wants.
A repelling spell, Impervius causes spells to bounce back at the caster.
A counter to the vanishing spell Evanesco, Inanimatus Conjurus can recover objects that were hidden.
Incarcerous can imprison the target by tying the person up using ropes.
Incendio creates fire.
Tarantallegara makes the target's legs shake violently.
Lacarnum Inflamarae causes an orb of fire to thrust out of the wizard or witch's wand.
A spell invented by the Half-Blood Prince, Langlock causes the target's tongue to be attached to the roof of their mouth.
Legilimens allows the wizard or witch to view the thoughts and memories of the target.
Levicorpus causes the target to be hung upside down by their ankles. It is thought to be invented by the Half-Blood Prince.Liberacorpus
Liberacorpus is used to stop the effects of Levicorpus (above).
Locomotor causes an object to levitate and move to wherever the wizard or witch wants to. However, to cast this spell, you must include the object's name, such as "Locomotor Book."
Not related to Locomotor (above), Locomotor Mortis causes the target's legs to be immobile.
Used like a flashlight, Lumos creates a stream of light to appear at the head of the caster's wand.
Lumos Maxima is the same as Lumos (above), but causes a larger beam of light to appear.
Lumos Solem is the same as Lumos and Lumos Maxima (both above), but the light that appears is said to be as bright as the sun.