In theoretical physics

Theoretical physics

Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...

, the term dressed particle refers to a bare particle

Bare particle

In theoretical physics, a bare particle is an excitation of an elementary quantum field. Such a particle is not identical to the particles observed in the experiments: the real particles are dressed particles that also include additional particles surrounding the bare one....

 together with some excitations of other quantum fields that are physically inseparable from the bare particle. For example, a dressed electron

Electron

The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

 include the chaotic dynamics of electron-positron pairs and photon

Photon

In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...

s surrounding the original electron.

In radiobiology

Radiobiology

Radiobiology , as a field of clinical and basic medical sciences, originated from Leopold Freund's 1896 demonstration of the therapeutic treatment of a hairy mole using a new type of electromagnetic radiation called x-rays, which was discovered 1 year previously by the German physicist, Wilhelm...

, a dressed particle is a bare particle together with its Debye sphere that neutralizes its electric charge.
Dressed particles are also often called clothed particles.