blood plasma, as the name suggests, is an ingredient of blood while the physical plasma is a mixture of free electrons ions and radicals in a quasi neutral electrical condition.

Blood has two components - the clear liquid and the corpuscles/cells entrapped in it. The clear liquid was named "plasma" by the famous Czech medical scientist (physiologist), Johannes Purkinje (1787-1869).

In 1927, Irving Langmuir- the American chemist  was exploring ionized gases (i.e. gases subjected to strong electric field to knock out the electrons from gaseous atom). He used the analogy of blood, with the ions being the corpuscles and the remaining gas being a clear liquid and named the ionized state of a gas as plasma. Thus, this name prevailed.

thank you for sir ...johannes and N.N.Misra