To ossify is to become bony or to turn into bone or bony tissue, or to stop developing and become stagnant.(verb)
See ossify in Webster's New World College Dictionary
See ossify in American Heritage Dictionary 4
verb os·si·fied, os·si·fy·ing, os·si·fies verb, intransitive
Origin: Latin os, oss-, bone; see ost- in Indo-European roots
Origin: + -fy.
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