Epistaxis. Today was the first time I heard that term.
Bits from Wiki:
For the plant referred to as "nosebleed plant", see Yarrow.
Epistaxis (or a nosebleed in plain English) is the relatively common occurrence of hemorrhage from the nose, usually noticed when the blood drains out through the nostrils. (Oh, yeah, I can attest to that.)
There are two types: anterior (the most common), and posterior (less common, more likely to require medical attention). (Yup, got the posterior.) Sometimes in more severe cases, the blood can come up the nasolacrimal duct and out from the eye. (It can and does.) Fresh blood and clotted blood can also flow down into the stomach and cause nausea and vomiting. (Lost the best part of a great sandwich SWMBO made for dinner.)
The flow of blood normally stops when the blood clots, which may be encouraged by direct pressure applied by pinching the soft fleshy part of the nose. This applies pressure to Little's area, the source of the majority of nose bleeds and promotes clotting. Pressure should be firm and be applied for at least five minutes and up to 20 minutes; tilting the head forward will help decrease the chance of nausea and airway obstruction. (It no worky. I lost the better part of a pint of blood over the last two days.
If bleeding is still uncontrolled or no focal bleeding point is visible then the nasal cavity should be packed with a sterile dressing, which by applying pressure to the nasal mucosa will tamponade the bleeding point. (They shoved a tree into my sinus cavity. I can feel it touching the back of my skull. It will be there until Saturday. Percocet is your friend.)
I'll be out of action for a few days.
edited to correct errors caused by nausea when I was typing.