ossification
os.si.fi.ca.tion \.a:s-(*-)f*.-ka--sh*n\ \a:-'sif-i-k*-.to-r-e-, 'a:s-(*-)fi-, -.to.r-\ n 1a: the natural process of bone formation 1b: the hardening (as of muscular tissue) into a bony substance 2: a mass or particle of ossified tissue 3: a tendency toward or state of being callous or conventional in outlook - os.si.fi.ca.to.ry aj