HARDRON IS...
A hadron is any particle that is made from quarks, anti-quarks and gluons. (If you want to learn more about quarks and gluons, start here.)
Point out** Each hadron has large number of gluons and of quark-antiquark pairs, plus something else. The something else may include...
- Three quarks of various types
- Three anti-quarks of various types
- A quark and an anti-quark, possibly of different types
- Extra energy, distributed among the many quarks, anti-quarks and gluons.
HADRON THERAPY IS...
Radiation therapy is the medical use of ionizing radiation to treat cancer. In conventional radiation therapy, beams of X rays (high energy photons) are produced by accelerated electrons and then delivered to the patient to destroy tumour cells. Using crossing beams from many angles, radiation oncologists irradiate the tumour target while trying to spare the surrounding normal tissues. Inevitably some radiation dose is always deposited in the healthy tissues.
When the irradiating beams are made of charged particles (protons and other ions, such as carbon), radiation therapy is called hadrontherapy.
Ref:
http://enlight.web.cern.ch/what-is-hadron-therapy