Lesser restoration, and a more limited version known as restore strength, were conjuration and necromancy spells (respectively) that removed a temporary handicap caused by certain creature attacks, poisons, and magical effects.
The necromantic version of this spell, restore strength, could only alleviate temporary losses of strength, whereas the conjuration version returned lost strength, constitution, dexterity, intelligence, wisdom, or charisma (only one of these characteristics per casting of lesser restoration). Using strength loss as an example, these spells could restore some or all of the losses due to chill touch, ray of enfeeblement, ray of fatigue, the excretion of a roper, the touch of a shadow, spider venom, and similar debilitating effects. The conjuration version also alleviated fatigue or revitalized an exhausted state to be merely fatigued.
Permanent losses, or losses due to a physical injury, disease, or other natural causes were not restored by these spells.