Correct spelling for the English word "Inspersion" is [ɪnspˈɜːʃən], [ɪnspˈɜːʃən], [ɪ_n_s_p_ˈɜː_ʃ_ə_n] (IPA phonetic alphabet).
Sprinkling with a fluid or a powder.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "inspersion" is not commonly used in the English language, and there is limited information available about its etymology. It is possible that you might have encountered a rare or specialized term specific to a particular field or usage.
However, there is a similar word that may have been mistaken or confused with "inspersion". The term "aspersion" is more commonly used and refers to the act of making false or damaging statements about someone or something. "Aspersion" comes from the Latin word "aspersio", meaning "a sprinkling" or "a scattering". In its original usage, "aspersion" referred to the sprinkling of holy water during religious ceremonies. Over time, its meaning expanded to include the figurative sense of casting doubt or criticism upon something or someone.