Miasm stems from the Greek word for pollution, stain to pollute. 

Before the germ theory connecting micro organism to diseases was accepted, miasm was a commonly used term for the cause of diseases, we now call infections. 

With miasm a dangerous influence or atmosphere was indicated as responsible for contamination or pollution causing sickness, death or decomposition. 

Hahnemann describes Miasms as negative forces that served no purpose other than to guarantee human a miserable life and an untimely death. Miasmatic thinking was fuelled by the limitations of homoeopathic cure and proposed by Hahnemann to explain why patients relapsed. 

Different types of Miasms in Homoeopathy : 

1. Psora   

2. ⁠Sycosis 

3. ⁠Syphilis       

Psora had affected almost everyone on the planet up to that time.     Contamination occured most frequently at childbirth or during breastfeeding. 

Hahnemann used the term "acute miasm" for all such acute infectious diseases. In aphorisms 73 of the organon (6th edition). He mentions acute miasm as recurring in the same manner.

1. Psoro –Hahnemann explained Psora as a diseased condition or disposition to disease transferring from generation to generation for thousands of years behaving as a fostering soil for almost every possible diseased condition. 

2. ⁠Sycosis - According to our Master Hahnemann the chronic miasm of venereal origin causing growths of the skin and mucous membranes.      

3. Syphilis - All types of destructive pathological diseases are the expressions of syphilitic miasm. Before destruction syphilis will present with inflammation and cutting of the nourishment and oxygen supply at cellular level. Syphilitic miasm is characterized by interaction, necrosis and destruction of the suffering organ.