Incarcerous Spell

"Thin cords shot from Lupin's wand this time, and next moment, Pettigrew was wriggling on the floor, bound and gagged."

— Description^[src]

Incarcerous is the incantation of a spell that conjures ropes to be used to bind the victim^[1].

Known uses

Quirinus Quirrell used this spell non-verbally on Harry Potter in 1992, during the Attack in the Underground Chambers.^[2]
In 1994 Severus Snape non-verbally conjured ropes to bind and gag Remus Lupin while in the Shrieking Shack.^[3]
Remus Lupin in 1994 used this spell to bind and gag Peter Pettigrew in the Shrieking Shack, after forcing him out of his Animagus form.^[3]
Severus Snape uses this spell on Sirius Black when he finds him unconscious next to Hermione Granger and Harry Potter under the influence of Dementor.^[3]
Peter Pettigrew conjured ropes to bind Harry Potter to Tom Riddle Sr.'s gravestone in 1995.^[4]

Albus Dumbledore applies this spell at Crauch Barty Jr. when he reveals that he ran away from the Azkaban and that he helped Lord Voldemort to capture Harry Potter.
Dolores Umbridge conjured ropes to strangle a centaur named Magorian, during the Skirmish in the Forbidden Forest.^[1]
Harry Potter conjured ropes which bound an Inferius in the Horcrux Cave in 1997, before the Battle of the Astronomy Tower
In 1997 Harry Potter used this spell to conjure ropes in a failed attempt to stop Severus Snape fleeing from Hogwarts, during the Battle of the Astronomy Tower.
Antonin Dolohov used this spell during the Luchino Caffe Duel against Ron Weasley in 1997.^[5]

The incantation "incarcerous" most likely derives from the Latin word "incarcerus", meaning "to jail" or "to imprison".

In the books, the ropes simply wrap themselves around the centaur's arms and chest; in the film, they also encase his throat, slowly strangling him and forcing him to the ground.
In the film adaption of Harry Potter and The Deathly Hallows:Part 1, a Snatcher is seen casting this spell on Ron Weasley who is bound in chains, of course it could have been a similar spell such as "Incarcereta" but it seems most likely that it was Incarcerous.
Also in the film adaption of Harry Potter and the Deathly Hallows:Part 2, while fighting their way down to the boathouse, Harry is seen casting this spell where a great flash of orange light escapes his wand and a Death Eater that was trying to lunge at him was instantly bound in chains, again it is unclear if this was Incarcerous or a different capturing-type spell.
An etymologically and functionally related spell is Incarcifors, which transforms objects into prisons to restrict a person's movement.
Based on conjecture, it is likely that Relashio or Emancipare could act as counter-spells to Incarcerous. The Revulsion Jinx would be able to release a person from the binding ropes of Incarcerous, while the incantation for Emancipare is derived from Latin for "set free", suggesting its ability to release a person from any form of incarceration.