The word "ossifluence" is not a well-known term and is not commonly used in everyday language. Its spelling can be explained using the International Phonetic Alphabet (IPA). The first syllable "ossi" is pronounced with a long "o" sound as in "bone" and a short "i" sound as in "fit". The second syllable "fluence" is pronounced with a "fl" sound as in "flee" and "uence" rhymes with "wince". Overall, the word is pronounced as "ah-si-floo-ents".
Softening and removal of bone substance; osteolysis.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.