About

Possible name origin: 'Poppy' refers to the opium poppy used in healing (Culpepper); 'Pomfrey' might refer to the medieval herb comfrey, used to aid blood clotting and for expelling phlegm (Culpepper).
Voice: stern, but kind to patients.
Age: middle aged, older than Sirius, James, etc., since she was nurse at that time.
Field: medicine.

The Hogwarts school matron (U.S.: “nurse"), who is very adept with curing spells, potions, herbs, and other remedies. Harry thinks of her as “a nice woman, but very strict” (PS17). Among other things we’ve seen her regrow bones (CS10), cure a poisonous dragon bite (PS14), fix Eloise Midgen’s nose after she cursed it off (GF13), remove beards (GF16), and shrink overgrown teeth (GF23). In fact, she’s only been stumped once – by the pimple charm, cast by Hermione, that left the word “SNEAK” tattooed on Marietta Edgecombe’s forehead. Madam Pomfrey “couldn’t make the slightest improvement” to that one, though one wonders how hard she was really trying (OP2 cool . It is true, though, that patients with severe injuries are transferred to St. Mungo’s (OP32), and that Dumbledore trusts Snape more than Madam Pomfrey to heal injuries sustained by severe Dark Magic (HBP13).

During the Battle of Hogwarts Madam Pomfrey organized the evacuation of underage students and treated the wounded (DH33).

Madam Pomfrey works hard to protect her patients’ peace and quiet, not hesitating even to throw out Dumbledore over an excited patient (PS17). When she is overruled on this front, she becomes very agitated (PA21). She has been the matron at Hogwarts for a long time, as she was there when Harry's parents were in school (PA1 cool .

Examples of Madam Pomfrey's healing:

She fixed Neville's broken wrist "in about a minute." (PS9)
Healed Ron's hand after he was bitten by Norbert (PS14)
Cures colds with Pepper Up Potion (CS cool
Re-grows the bones in Harry's arm (CS10)
Treats the children Petrified by the Basilisk (CS10)
Restores Hermione's appearance after she accidentally uses Polyjuice Potion with a cat hair (CS12)
Tried to treat Harry after the Dementor attack only to find that Lupin had already administered chocolate (PA5)
Treated Draco's arm after he was attacked by Buckbeak, though Draco wore a sling for weeks afterward (PA)
Healed Harry after the Dementors attacked Harry during a Quidditch match and caused him to fall from a very high altitude (PA9)
Protected Lupin by walking him out to the Whomping Willow every month when he was about to transform (PA1 cool
Treated Ron when the Whomping Willow broke his leg (PA21)
Fixed Eloise Midgen's nose back on (GF13)
Removed the beards from Fred and George when they failed to fool the Goblet of Fire (GF16)
Cleans Harry's shoulder wound from the Horntail with a purple liquid that smokes and stings and puts an orange paste over Cedric's burns (GF20)
Shrinks Hermione's curse-enlarged teeth (GF23)
Bundles up the champions and the people they rescued from the bottom of the lake after the second task (GF26)
Fixed Alicia Spinnet's eyebrows after Miles Bletchley jinxed them to grow uncontrollably (OP19)
Calmed Hannah Abbott when she became distraught over her O.W.L.s (OP27)
Cannot remove Marietta's pimples that spell "SNEAK" (OP2 cool
Helps Montague return to normal after being stuffed in a Vanishing Cabinet (OP32)
Helps Professor McGonagall after she is Stunned by Umbridge's henchmen (OP31)
"Patches up" Luna, Neville, Hermione, Ron and Ginny after the Battle of the Department of Mysteries (OP37)
Even helped Umbridge recuperate after she was attacked by the Centaurs (OP3 cool
Helped Katie Bell after she touched Draco's cursed opal necklace (Katie was later transferred to St. Mungo's) (HBP12)
Cured Ron with essence of rue after he drank poisoned wine meant for Dumbledore (HBP18, 19)
Quickly fixed Harry's cracked skull suffered during a Quidditch match (HBP19)
Treated Bill Weasley's wounds with "harsh-smelling green ointment" after he was mauled by Greyback (HBP29)
Treated the wounded during the Battle of Hogwarts (DH33)
Films:
Harry Potter and the Chamber of Secrets: Madam Pomfrey was played by Gemma Jones.